@vw9ycxxz1bf4 The only apps I see enabled at startup are and AMD utility and a component of the Realtek audio driver, and both should stay enabled. 26% memory use is a bit high but not concerning, and it shouldn't cause problems with Sims 4. The 52% use once you're in-game is pretty much exactly what I'd expect: Sims 4 will normally use about that much RAM in a new or lightly-played save.
A longer-term save might use something in the range of 6 GB RAM, but it shouldn't go above 10 GB and then run out of memory, which is what it sounds like is happening with you. I'm guessing this only happens in a save you've previously played, but please do let me know if it happens in a new save as well.
For the affected save, it's possible a mod did some damage before you removed it. One possible cause of high RAM use is too many sims in the background, which is easy to check if you're willing to add another mod (temporarily). Download Show Sim Info, the one by Frankk (not the MTS version, which is outdated), click a sim, choose "search all sims," and let me know how many you see.
If the number is higher than 1,000, please load your oldest backup copy of this save and see how many sims are in it as well. Here's how to load a backup:
https://sims4.crinrict.com/eng/2014/09/recover-backup-save-game/
Memory use returning to 21% after the crash is exactly what you'd want to see. That means the problem is entirely contained to Sims 4.