Thank you for the latest idea but that didn’t work either. Another thing I tried was to quit to the Main Menu and try to exit that way, but it still froze with the black screen. I’m running out of things to try.... I’m not even playing the game anymore because I feel challenged to find out what the problem is and fix it, haha. :p
Not to mention, it’s a bit of a boring game without being able to install any store venues or worlds.
It was interesting that back in Fall 2016, some Sims 4 players were experiencing a similar issue:
https://forums.thesims.com/en_US/discussion/919091/game-crashes-upon-save-exit