This sounds like the motion smoothing is heavily solicitated and can’t keep up.
you might want to read this:
My 2070 SUPER VR settings and suggestions (Index - SteamVR) 🟢 - #572 by CptLucky8
Hint: I don’t know what your video card is but you might want to start with Motion Smoothing Fixed Rate, 90Hz/18fps/33ms (the prediction setting is very important for motion smoothing). It won’t eliminates motion smoothing artifacts but after a while you get used to them.