[grumbel]

No, the games just disappear from the shop and can no longer be bought via Steam. When you are already own them, you keep them. Third party seller might sometimes also still sell remaining Steam Key inventory and thus offer a way to activate a delisted game on Steam.

One area where content can disappear is music licenses, those often don't result in a complete delisting of the game, but just the music getting patched out of the game. In those cases, the music would be gone for everybody, as Steam game updates are mandatory and you can't downgrade the game to a previous version either. Unofficial mods will sometimes address this issue and add the music back in.

[Fluorescence]

> Steam game updates are mandatory and you can't downgrade the game to a previous version either.

For Crusader Kings III, the old versions are listed as betas (cog -> properties -> betas) so you downgrade by "signing up to a beta".

I don't know if it's a common practice but pretty damn necessary for paradox games. A single game might take months and their attitude to backwards compatibility is "new versions will corrupt your game files in ways that only subtly reveal themselves like noticing the King of England owns a county in Mongolia before reaching a game year that will always crash".

[duskwuff]

> Steam game updates are mandatory and you can't downgrade the game to a previous version either.

You can usually download old versions from the CDN using tools like steamcmd. Developers can remove the old depots, but usually don't.