I'm pretty sure (at least I hope!) this update retroactively has the previous fixes as well and they just didn't add all the lines into the changelog.

I certainly hope so. However, the previous GOG update's changelog (November 21st) did include all the lines of the previous Steam updates all together. Hence me doubting this.

Perhaps there is a way to validate this by checking some of the fixese applied between Feb 12th - March 23rd. Three of the changes are:
1. Added Korean language
2. A selection of loading screens now have progression bars
3. Pause menu is redesigned

Changelog for Update 1.04 (added 17 September 2018):

General
* Fixed selecting the Lava Cake act in Alpine Skyline taking you to The Birdhouse

The Arctic Cruise
* The Arctic Cruise Act 2 & 3 no longer requires Death Wish stamps
* Fixed a softlock in Bon Voyage! with the Mafia in the dinner hall
* Ship Shape (The Arctic Cruise) has had its balance tweaked, so that (hopefully) no player should be stuck on it for hours

Death Wish
* Peace and tranquility (easy mode) now costs 77 pons instead of yarn
* * Fixed a bug where peace and tranquility could not claim rewards or be refunded
* 3-Lives requirement has been removed from all Death Wishes except Rift Collapse and Boss Rush
* 3 lives are disabled in peace and tranquility
* Fixed a bug where timer challenges were unaffected by peace and tranquility
* So You're Back from Outer Space's primary objective has been made easier in easy mode
* UFOs in So You're Back From Outer Space have been made a bit easier to avoid
* Peace and tranquility can now be turned on the moment its available by holding A, you no longer need to exit to menu
* 10-Seconds to Self-Destruct and Bird Sanctuary now have peace and tranquility

Update 1.05 (21 September 2018)
- Ship Shape's requirement has been reduced from 20 to 18 (40 to 27 in co-op).
- Peace and Tranquility has been assigned another button instead of A
- Fixed a softlock in Boss Rush
- Death Wish Mafia Boss no longer pushes the player away into sandbags
- Boss Rush lives have been redesigned. You can now retry a boss in Boss Rush up to 3 times, after which you return back to the first boss.
- Peace and Tranquility now no longer shows after 50 deaths (but you should definitely turn it on if you're this deep)
- Death Wish now counts as 110% on the save file and is no longer required for 100%.
- Modding is now enabled by default again
- Punished Kid achievement stamp requirement has been reduced from 70 to 50

Changelog for Update 1.07 (added 01 October 2018):

An update to A Hat in Time is now available!

* Blueberry Pie, Forest Critter and Minty Fresh can now once again be obtained
* Fixed a bug where having mods installed that utilize localization would slow down the game
* Added a standard and high quality ambient occlusion setting
* Fixed a bug where resetting a Death Wish parenting an active passive Death Wish would not deactivate the passive Death Wish (such as Zero Jumps)

Changelog for Update 1.08 (added 18 October 2018):

* Fixed co-op softlocks in Battle of the Birds
* Co-op characters now have a health pon hover around them when they pick up health, for the other player to pick up
* Several performance improvements
* Editor: Fixed a memory and performance leak in Note actors

Changelog for Update 1.09 (added 04 November 2018):

General
* Fixed a bug where DLC would sometimes not be recognized mid-game if the internet connection of the player was unstable
* Fixed some particles appearing incorrectly on some systems
* Beach balls are fun
* As per community request: Added "Hold Backwards to Cancel Diving" option in Input Settings
* Speedrunning: Bag Skip is back (we were able to apply a fix for the casual issue it caused without patching the exploit itself)
* DLC is no longer required for a 100% save file if the player doesn't have the DLC installed
* Minor improvement to loading times
* Fixed a crash on Windows systems with no mice like tablets
* Fixed a bug where exiting the Time Rift reward screen prematurely would make the game stop rendering

Co-op
* A new co-op feature is now available: Fullscreen co-op! It can be turned on in game settings
* Fixed a bug where entering the settings menu as the co-op character would result in weirdness

Titlescreen
* Several performance improvements

Spaceship
* Fixed small hitch when interacting with the Rift Token machine

Mafia Town
* Heating Up Mafia Town: Fixed a selection of trees being invisible but still having collision
* Several performance improvements
* Fixed the button in Mafia HQ being wonky

Battle of the Birds
* Fixed disco balls exploding too early in the Battle of the Birds boss battle
* The input menu for controllers now has the missing numbers 0, 8 and 9
* The Big Parade: Several performance improvements

Subcon Forest
* Moved a floating minion to land in the swamp area
* Fixed a bug where Snatcher's theme would continue to play in co-op even after exiting his trap
* Several performance improvements

Alpine Skyline
* Several performance improvements
* Fixed fog colors not appearing correctly
* Improved a part of The Windmill Death Wish where birds rode on a moving platform
* Fixed control being inverted on the telescopes

The Arctic Cruise
* Improved performance of lens flares
* Fixed a bug in Rock the Boat where it was possible to enter the water without freezing
* Fixed a bug where the game would freeze for 1 frame as the level was fully loading
* Deep Sea Time Rift: Several performance improvements

Time's End
* Several performance improvements
* Fixed a bug where Mustache Girl would rotate very oddly while using her laser attack

Changelog for Update 1.01 (added 12 May 2019):

General
* Korean localization has been updated
* Fixed a few typos in Nyakuza Metro and Online Party
* Dancing Online Party players now properly animate in gifs
* Fixed a bug with using the Camera Badge while the emote HUD was open, causing the game not to pause
* Fixed the end-of-Time Rift reward giving Hat Kid rewards when playing as Bow Kid
* Fixed Badge Seller music not stopping when purchasing an item and then exiting
* Fixed shop descriptions sometimes not matching the item when using mouse & keyboard
* Fixed being able to dance and carry items at the same time
* The kids now stop dancing when weapons are swapped

Online Party
* Fixed not being able to select The Illness Has Spread in Online Party
* Players who did not participate in an act at all are no longer on the end-of-act scoreboard
* Player avatars were temporarily disabled, but are now back
* Based on community-feedback, guest parties have been increased from 4 slots to 6. Overall we heard a lot of reports of players feeling like they never met anyone using the guest feature, so we hope this will improve the chances of meeting a stranger. We may further adjust the guest party sizes moving forward.
* Fixed Online Party players showing up in the game's ending, and while in tutorial scenes with Mustache Girl / Cooking Cat
* Fixed being able to use emotes as Mustache Girl during the sequence before The Finale, causing her to T-pose
* Added the option to mute other players' emote sounds in Game Settings
* Fixed a soft-lock caused by pausing the game while the prompt to join an act was visible
* Fixed Bow Kid not having the Online Party crown
* Fixed being able to join acts for chapters the player didn't have unlocked
* Fixed player list not displaying anything if no avatar can be loaded from remote
* Fixed being able to interrupt talking players by hitting them

Nyakuza Metro
* Fixed a Relic in a crate that would permanently disappear.
* Fixed crows attacking respawning player in green station

Spaceship
* Fixed a hole in the storage room that could result in players falling into the void

Mafia Town
* Fixed the button in Mafia HQ not opening the gate if another Online Party player stepped on it
* Fixed the Heating Up Mafia Town faucets spewing lava outside of the correct act
* Removed invisible raccoons that would attempt to attack the player (but wouldn't actually hurt the player)

Alpine Skyline
* Fixed Time Rifts being unavailable
* Fixed the Free Roam titlecard being incorrect

The Arctic Cruise
* Removed impossible-to-get relic in Arctic Cruise finale

Death Wish
* Bird Sanctuary: Fixed exploding eggs sometimes counting a penalty despite no birds being harmed
* Fixed a bug in the "Collect every Rift Pon" bonus objective for Rift Collapse, making it unclearable
* Fixed some objectives done with Peace and Tranquility not counting on the main menu (however they would count correctly after having entered the game)


The 1.01 is misleading as it's the actual latest version of A Hat in Time - Nyakuza Metro.

Changelog for Update 1.02 (added 15 May 2019):

General
* Chinese localization has been updated with Nyakuza Metro support
* Korean localization has been updated
* Several memory improvements
* Fixed a rendering thread crash
* Fixed rare stickers sometimes not spawning
* Fixed rare stickers in Mafia Town only being available in the daytime acts
* Fixed main menu cutting off for ultra widescreen
* Save files are now automatically backed up once per day
* Added an option to disable the emote wheel
* Fixed "Return Home" achievement not working

Nyakuza Metro
* Spoiler: Fixed a bug where selecting Nyakuza Metro finale before having seen the finale cutscene would jump straight into the finale act, leaving the player clueless as to what had happened
* Fixed Nyakuza Metro - All Clear! achievement not triggering if Rumbi Factory was completed as the last Nyakuza Metro act

Spaceship
* Fixed softlock with Cooking Cat's tutorial and having auto-skip cutscenes on
* Fixed a bug where loading a pre-DLC branch of the game caused certain relic stands containing new DLC relics to become unavailable


Note: Update is labelled as 1.02 but that's the latest version of just A Hat in Time - Nyakuza Metro

Changelog for Update 1.04 (added 20 May 2019):

General
* Fixed inconsistent rare sticker alerts
* Added a machine in the spaceship which reads back the latest rare sticker alerts
* Updated Chinese localization
* Updated Korean localization
* Fixed massive log files when mods would continuously emit the same error
* Fixed a save data crash

Spaceship
* Fixed the intro camera looking at the attic before it was unlocked

The Arctic Cruise
* Fixed a missing rare sticker

Nyakuza Metro
* Fixed a crash caused by bouncing one of the queuing cats into a vacuum

Changelog for Update 1.05 (added 27 May 2019):

- German localization for Nyakuza Metro
- Fixed Korean translation being mis-labelled in credits
- Updated Korean localization

Changelog for Update 1.06 (added 06 June 2019):

General
- Updated Korean localization
- Updated German localization
- Fixed a bug causing Steam to be a bit too aggressive in making sure your game is verified

Death Wish
- Fixed candle Death Wishes not working during specific circumstances
- Fixed Boss Rush allowing to resume at the boss you died at even after losing all lives

Standalone installer updated: 10 June 2019.

Update 1.11 (04 September 2019)

General
- Improved texture compression quality of Time Rift pages
- Improved performance of Blue Time Rifts
- Fixed some outfits and flairs having the wrong texture group
- Significantly reduced stutter and pop-in for level intros
- Improved stability and overall performance

Seal the Deal
- Tour Time Rift now emits its intruder alert continuously until cleared

---

Update 1.12
N̶o̶ ̶c̶h̶a̶n̶g̶e̶l̶o̶g̶ ̶p̶r̶o̶v̶i̶d̶e̶d̶ ̶h̶e̶r̶e̶ ̶(̶y̶e̶t̶?̶)̶,̶ ̶b̶u̶t̶ ̶t̶h̶e̶ ̶f̶o̶l̶l̶o̶w̶i̶n̶g̶ ̶i̶s̶ ̶w̶h̶a̶t̶ ̶w̶a̶s̶ ̶p̶o̶s̶t̶e̶d̶ ̶e̶l̶s̶e̶w̶h̶e̶r̶e̶.̶
Finally got added here, missing a few things as expected.

Update 1.12 (23 January 2020)
- Performance and stability improvements
- Added a new visual for when multiple screen-altering badges are equipped (thank you to Ova for allowing us to take inspiration in their video)
- Fixed a ladder that Hat Kid didn't feel like climbing in The Windmill (Alpine Skyline)
- Fixed some metro trains suddenly and unexpectedly appearing in Nyakuza Metro

Yesterday I got a new update, "GOG final"?

I kinda don't like the name "GOG Final" that almost tells me they won't update it again if there happens to be another update for Steam.