Also, Atari's official announcement on January 23 (again, easily searchable on the GOG forum I mentioned and Atari's official subreddit), stated that the studio's own development tools, don't allow for this content to be efficiently replatformed to GOG and VCS.

There could be some credence in this statement, at least in regards to Digital Eclipse's previous approach in repackaging the Disney Collection on GOG, where, instead of adding the additional game, that Steam users got as an update (?), Digital Eclipse replaced the original collection with the full version that Steam users have.

Which begs the question, why not re-release Atari 50 on GOG as the 'Expanded Edition'?
Again, this could be related to my previous theories.

Last point: if we look at the' holiday update' Atari released on Dec 5 2023, where DE dded 12 new games, this update involved a 12GB (?) install. Essentially, downloading the entire game again, for games and their high resolution covers, taking up MBs.
Of course, this is an inefficient delivery model. I believe this same update method was on the Steam version.
This model of delivery, is developer dependent.

This update method, as well as the previously mentioned Disney Collection repackaging approach, may be indicative of Digital Eclipse's proprietary development tools.

For everyone else: search Atari's statement on their VCS subreddit.

If other users on here can't find the official Atari announcement, then of course I will send this.

If one reads my posts, though they are rather lengthy, a goal of mine is to help raise awareness of the endemic issues I have mentioned regarding longing standing update issues on GOG, and part of my drive - which, concerns all of us, as consumers, is to encourage a proactive approach in researching pertinent information.

Unfortunately, some users seem to simply expect information handed to them on a silver platter - and when, instead, a proactive approach is suggested, they seem offended by this, to the extent of outright dismissal of the relevant channels I tried to provide. For example, implying that I suggested to 'blindly trust ' Reddit. How can you 'blindly' trust Atari's official subreddit? Unless this user was unaware of Atari having their own subreddit in the first place. Again, awareness, or lack of.

Unfortunately, when these requests - for easily obtainable information - are not acceded to, the forum posting etiquette card is waved, repeatedly.
Again, context is key to understanding meaning, and my post regarding Atari's announcement, wasn't me 'claiming news' - this is not 'news'. This announcement has been in the public domain an entire month since this forum was created by this very user.
The point to my post, was rather, quoting my message to GOG Support, in detailing a possible solution to the issue of missing DLC.

Again, I have made significant contributions to this and the 'Wider World of Atari' forum and I hope to continue to do so.

Of course, they didn’t release the DLC on here. This is precisely the point.

Atari would have had the sales figures from the main platforms since the initial DLC release 6 months ago, and DLC 2 just over a month later to make that decision (whether it was viable to release the DLC). As I said though, this is just speculation.

We are not privy to the internal processes between developer / publisher / store, marketing / financial decisions, technical feasibility. There are no doubt multiple factors at work in deciding to release a game / DLC.

Atari / Digital Eclipse' Jan 23 statement on the cancellation of updates / DLC for 'Atari 50' for the GOG and VCS platforms,

The full Discord statement, located on Atari’s official VCS subreddit:

https://www.reddit.com/r/AtariVCS/comments/1i8d6qg/atari_50_dlc_cancelled_for_atari_vcs/

"The studio's proprietary development tools don't allow for this content to be efficiently re-platformed to the VCS and GOG platforms".

Regarding this specific statement.
How come this content (DLC) needs to be "re-platformed" to VCS / GOG ?

'Atari 50' did not require native development. This was released on the same date and even time, as the Steam version.
This was / is a multiplatform approach. From a development standpoint, this would make sense in terms of reducing development costs, shortening development timelines and ensuring consistency.
Why would DE not use a multiplatform approach? They absolutely do.

The 2 DLC packs were released simultaneously, across multiple platforms, of different hardware architectures - for every platform going.
Clearly, this was a multiplatform development approach, using a single codebase. This is crucial for businesses for achieving wider audience coverage without doubling development efforts.

Again, going back to the 'holiday update ', this was free DLC. GOG got the update almost at the same time as the Steam version. If not on the same day.

So why, after a historical pattern of multiplatform development of Atari 50, free DLC ('holiday update') including the DLC packs, did the DLC suddenly become a 'native' codebase, needing to be 're-platformed'?
What is fundamentally different about code meant to run on PC architecture with the Steam version, that can't also run on a PC for the GOG version?

Ok, let's give Digital Eclipse the benefit of the doubt for a moment. They wrote the codebase for the 2 DLC packs, for every platform under the sun, apart for VCS (Atari's own hardware customers) and GOG. Both of which have already purchased the base game 'Atari 50'.
At the very least, this highlights either / and complete neglect of these customers, or a complete oversight on Digital Eclipse' part - to not factor in these platforms in their multiplatform codebase.
Again, despite DE accommodating GOG before with the free DLC ('holiday update'), they then 'forgot' how to integrate GOG back into the codebase.

This whole situation becomes more and more ridiculous the more we look at it, especially when we look at the conflicting statements from Digital Eclipse from day one, that "something went wrong" [with the GOG DLC failing to launch along with the main platforms] that they were trying to "fix" - Digital Eclipse' comment on the YouTube trailer video for DLC 1:

https://youtu.be/NITMbBSbUoc?si=Pdw4uzS0HwxsN_7S

then after 6 months of "actively trying to resolve the issue" -
Atari's response:

https://www.gog.com/forum/atari_50_the_anniversary_celebration/wider_world_of_atari/page2

- to Digital Eclipse' / Atari's statement on Jan 23, that there isn't an active project after all (above Discord statement / link).

The multiplatform development code, which is essential to businesses in modern gaming development, to then needing to be "re-platformed".