Re: Sims 4 endlessly stuck on loading screen
There's further troubleshooting you should try:
Move/rename the Sims 4 folder in Documents > Electronic Arts then launch the game. Quit at the main menu, don't bother saving. A new Sims 4 folder will have been created in the Electronic Arts folder. COPY the save that has the problem household from the Sims 4 > saves folder you moved/renamed to the newly created Sims 4 > saves folder.
Do you have the same problem?