I did quite extensive tests and the lag, fps loss, judder in resource extraction points is not related to CPU or GPU.
I can put 640 resolution and lowest settings and will experience the exactly same framerate as on 4k, ultra settings and 70% cpu clockrate.
It's a game engine issue which causes delays/waits during rendering that is not related to CPU or GPU power, it's either network performance or some other stuff that should not be done during frames.
They need to remove that pausing stuff from the rendering job and it should work fine.
Could be loading assets from disk. Even with SSD there's only so much bandwidth. I don't spend too much time at resource extraction sites. Does the judder get better over time when there? Or is it pretty consistent?