I prefer the chaos of devs randomly storing data in appdata, programdata, the program files dir, the x86 program files dir with mostly but not entirely duplicate data, c:/games/game/game and ../, c:/game/game, ~/games, ~/game/game &./game, ~/documents/game, ~/documents/games/game, ~/game saves/games, etc...
Special place in hell for games storing heavy or frequently modified files in user's Documents dir - nowadays, Documents is often a synced folder backed by OneDrive. The amount of wasted processing, bandwidth and IO wear generated by this is tremendous.
The one that I've always found odd is everything deciding to dump itself in the user profile directory (this is even something that stuff like VS Code does).
XDG_CONFIG_HOME (|| ~/.config) and friends has been a standard for a long time now on *nix (including macOS) and AppData (née Application Data) has been the standard on Windows for over 20 years at this point.
Other than saves, what files do games heavily modify? And if you're complaining about cloud syncing of (auto)saves, I personally think it's a good thing.
One example I experienced recently: Sims 4 uses a subfolder in Documents as a cache for downloaded data and decoded chunks. It creates and deletes files there constantly while the game is running; we're talking dozens of files per minute or more. Few minutes of play, and there's nothing but hundreds of new additions and deletions in the "recent history". Not to mention, all that auto-syncs with any other machine you have online and using the same Microsoft account.
Wrt. Saves, auto-uploading those can be good, but it's unnecessary for games I rent on Steam, which already handles cloud saves on its own.
