Ideally no. The file path should be [Users] > [your user account] > Documents > Electronic Arts > The Sims 4 so the game is storing the data locally on your Mac only.
When your Mac starts running low on storage it will start storing everything exclusively in iCloud if you have iCloud Drive setup and the box ticked next to Desktop and Documents in System Preferences.
But your mod issue may be just that, a mod issue rather than directory issue.