As of this AM with patch 6.45, Screen Space Ambient Occlusion in the System Config, Graphics Settings causes MAJOR stuttering issues not FPS loss even though it appears to be.

I have tested this on two computers, both Alienware.

Desktop: RTX 3080
Laptop: RTX 3070ti

32GB RAM
NVME

Windows 11 Pro

Drivers are up to date, did not do this before 6.45.