Most likely you are CPU bound. I have RTX 2080Ti. I recently upgraded from Ryzen 7 1700 to 3800X just because of this. With old CPU I could not run anything but lowest settings and still had major stutters in Spain city areas. Now with R7 3800x (only CPU swapped), I can run medium/high settings even in a city and dense forest areas of stages. And still, fpsVR (https://store.steampowered.com/app/908520/fpsVR/) is showing that I'm mostly CPU limited.
The takeaway is that VR is an extremely CPU demanding affair.