Solved
PSA: Use fullscreen mode, not borderless (performance issue)
I only just now realized that switching to fullscreen mode gives me way better performance than borderless. I jumped from ~60fps to 100+. My CPU and GPU utilization hovers at about 30% which is weird...
- Ok, it appears that the dynamic resolution scale option only works in fullscreen mode, and that's what was boosting my framerate in fullscreen mode. Disabling it yields the same framerate between borderless and fullscreen mode, so that must be it. I guess I'm satisfied with my current performance with the assumption that it'll only improve going forward.
