@ThisMicrophone Your old and new dxdiags both show that the graphics driver is crashing. I'm talking about these errors, at the end of the dxdiags:
Event Name: LiveKernelEvent
Response: Not available
Cab Id: 0
Problem signature:
P1: 141
P2: ffffc505b29ef210
P3: fffff8061efb9050
P4: 0
P5: 41e4
P6: 10_0_19045
P7: 0_0
P8: 768_1
P9:
P10:
More precisely, LiveKernelEvent 141 means that the video driver failed to respond in what Windows deems is an appropriate interval (2 seconds by default), so Windows resets the driver. The process is a bit more complicated, of course, but the point here is that the driver isn't bahaving appropriately when running some task.
If that task is a game known to work properly on the vast majority of systems and with the currently-installed driver version, then the problem is almost always on the user's system. That, in turn, doesn't necessarily mean that the graphics driver itself is the problem. But you've stress-tested the graphics card and verified the integrity of Windows, so the driver is the only good suepect left.
As for why this only happens in Sims 4, I couldn't tell you for sure, but I will point out that it's an older game that may use different runtimes and other resources than all the other games you play. So if the problem is with part of the driver that deals with DirectX 9 functions, and all your other games use DX11 or 12, you'd only see the problem in Sims 4.
Clean-uninstalling and reinstalling a driver is a very safe process and doesn't require any extra backup procedure. You'd of course want to have your essential files backed up anyway; I'm just saying that this isn't a special circumstance. DDU is widely used and extensively tested and is actually more reliable than the built-in Nvidia and AMD processes for cleanly removing a driver. You could of course uninstall the driver through Device Manager and reinstall the latest version, but if that doesn't help, and it might not, you'd end up needing DDU anyway.