The Sim's user data files being in the Documents folder is the most asinine thing I've ever heard of. Free OneDrive accounts (which a lot of people use) on Windows 11 forces the Documents folder to be synced with the cloud. The free OneDrive tier maxes out at 5gb, so it doesn't take long for the Sims to max out the OneDrive storage.
My Niece came to me and was asking why her OneDrive wasn't syncing any more. I finally figured out that this is why. So, I figured, ok, I'll just configure the Sims user data folder to be where I wanted it to be. But no, we're SOL.
Storing user data (especially data that can be many gigs) in Documents by default a terrible idea, not allowing it to be configured by the user is ridiculous. Unbelievable.