Anybody else get low GPU utilization (50%) in the Enhanced version on an RTX 4090?

After playing for about 20 minutes my framerate drops to around 80 FPS, and my GPU utilization to around 50%. Clearly it's bottlenecking for some reason but I don't know why. I'm using a RTX 4090 with DLSS performance so it should be easily able to achieve 120FPS.

Anybody else have this issue too on PC?