Just a friendly reminder.

edit: oh, and patches, source ports, etc for games

I've made a habit of downloading the offline installers as soon as I buy a game, and once a week I download them again if there have been updates. :)

At my library's current size, doing this manually doesn't really take a big effort.

And then every once in a while (should be more often, I admit) everything is copied to an external HD.

Indeed. If you back them up as you buy, download & play them, the effort is virtually unnoticeable. "Many Gamers (tm)" agree! Said what "Backup your data"? That's wise advice on any day. Microsoft / Google are still in business too, but that doesn't make people wrong for making local backups of important Gmail / Outlook emails. Games are really no different.

Edit: Leaving everything in the cloud also doesn't stop content alteration either. There are some games here like Don't Starve that I don't want the latest DLC and prefer the older version for being smaller, lighter weight and less buggy. There are others games like Divinity Original Sin and Obduction where the newest offline installer build is buggy but GOG now refuse to provide the older bug-free offline installers. And does anyone know how long Cyberpunk 2077's licensed songs are licensed for before they get "removed" GTA IV style?...

I never said not backup our data...what I mean is because the bad launch of CP2077 and that game that nobody knew about that didn't get released here people think that gog will shut down tomorrow....Even if gog does shut down they will give a people probably 1+ years to backup their data...We already have 50+threads about demolition..we don't need another 20+threads about backing up our data...I feel bad for the mods that will have a tough job cleaning this whole mess tomorrow and in the upcoming week

That's highly optimistic when even the User Agreement (17.3) says "we'll try and give 60 days", ie, well short of a year and no actual guarantee even for 1 day. Aside from the fact that when things are bad enough for an entire company to shutdown they often go very fast / may not even be under the same management / administrators brought in who'll be looking to minimise costs and go by what they're legally obliged to provide (0 days), etc, under such events the servers would be so overwhelmed that download speeds would plummet for everyone and those with larger collections may not get even half their games during such a time-frame.

Desura and Dotemu are gone. There was another store who sold drm-free games, but I bought only one game there so I forgot the name. Gamersgate started to replace drm-free games with steam-keys.

Dotemu anounced they would close their drm-free shop so you could donwload everything right in time. Desura on the other hand went down very quickly . There were always news that the site will go back online, never happened. Since a few weeks the site is online and you only find little online-games here.
https://en.wikipedia.org/wiki/Desura#Ownership_changes

And then there was of course that site relaunch of gog in 2010. GOG closed the site over the weekend with a message that the site maybe have closed forever. At the end it was a PR stunt justified with the statement how important backups are.
https://www.gamasutra.com/view/news/30541/Monks_Confirm_Good_Old_Games_PR_Stunt_Site_Relaunch.php

Edit: In case of Dotemu they announced in march the closure and that you had time to june to download all games, which are three months and not a year.
https://techraptor.net/gaming/news/dotemu-is-closing-their-online-store

yep with cyberpukk ive ran out of space :( possibly, but first day buyers got angry to fall for this beta release again, if only they could stop preordering games

It does hurt!

1. It puts extra stress to GOG servers if people are constantly downloading games they are not going to play there and then.

2. You might have to buy new bigger hard drives to fit all your GOG games into them!

So while it might be a good idea to backup one's games, it is simply not true it NEVER hurts! It hurts my walled that now I apparently have to buy a second 5TB USB 2.5" hard drive for my GOG game installers.

I think there was another called indiegamestand or so? They very suddenly shut down with some announcement about how they were unable to afford the servers any longer and could not come to an agreement with the host or so.

While I'm not gonna discuss the truthfulness of the OP I must say it provided a genuine LOL. xD

I have mine.

Oh, I remember that store too. I checked isthereanydeal and there was also ShinyLoot, which seems to be kind of a weird hardware shopping site now. And I'm pretty sure there was another indie gamestore like itch.io, maybe 5-6 years ago. At least I remember buying there an obscure episodic sci-fi game you got only there (which name I also can't remember, but I got backuped for sure).

So yeah, backup your stuff is always a good choice.

Twice, just in case (by that I mean backed up in two places).

Real men don't do backups. Real men cry