I definitely agree it’s GPU based, but if your card isn’t hitting it’s head on the cap, you aren’t getting VRAM or Texture cap issues, it could just be that the drivers are failing at higher utilization but that’s a hard call to make from just artifacting. Let’s see if it’s just heavy utilization, then we can lean into more drastic fixes.
Drop the scalability to low/medium and keep it there for an entire session and see if it takes much longer for this to appear. After that, try working until this appears, pop open another default scene and just place a couple of your meshes in and around to see if the memory ever gets released.