The Sims 4 won't launch because of the EA App

@trplcheeseburger  Please clear the EA App's cache:

https://help.ea.com/en-us/help/faq/clear-cache-to-fix-problems-with-your-games/

and restart your computer.  Then try to launch Sims 4 from the EA App or Steam, whichever one you used to install Sims 4.  If this doesn't work, restart your computer again and run both the EA App and Steam as an admin: right-click each desktop shortcut and select "Run as administrator."  Then try again to launch Sims 4 from the appropriate app's game library.