Forum Discussion
Shadohz You said you didn't know of another game that stores mods in the Documents directory. I mentioned the first one that came to mind.
My "I don't know how it would work" comment was about the fact that there are already files in ProgramData and AppData that need to be there for other reasons. And the EA App team is unlikely to completely reconfigure how the App works because the Sims 4 team wants to use one of these folders. Popular as it is, Sims 4 is not the only game being supported, and the App has enough existing issues without adding another variable or requiring a reorganization.
Regular players did have more trouble adding mods to Sims 2, or Sims 3 in the first year or so, when mods needed to be added to the game's program files. Of course they could learn, but fewer people did, relatively speaking, and more who tried ended up breaking things. The decision was deliberate with Sims 3, to make things easier for more of the player base, and it continued with Sims 4.
Personally I think user data should be in %UserProfile%\Saved Games, as it is with Respawn and many other developers, and also with the Sims 1 rerelease. (This is only about Windows of course.) But I don't think anyone working on Sims 4 is particularly interested in changing course now. Among other things, the player base would be confused and probably angry for a very long time. There would be a steady stream of players who came back after years and had no idea that anything had changed, and more who found older guides that pointed to the wrong location and were never updated. It still happens on this forum with Origin-related issues, and there has been plenty of messaging about the switch to the EA App in the last few years.