Edit: This seems related to vsync. Something's wrong with the rendering pipeline or buffers. Objects are several frames behind, or process a few frames, then pause. I've now observed this issue at 58-60 FPS, moving amongst trees, with no dynamic lights involved. All the trunks begin lagging for a few frames, then resume, lag, resume, etc... Disabling vsync resolved it. However, I would not recommend this, since it causes other issue and noticeable screen tearing, thus 'stutter' noticeable on hard edges and interiors.
When setting shadows to Ultra+ and foliage visibility to Ultra/Ultra+, scenes with dynamic lights in the near foreground seem to stutter a LOT more than they should.
FPS is still over 55, yet the visibile screen lag is much greater. A fine example is the crossroads with a shrine right after the last river before Crow's Perch.
While looking at Crow's Perch, from the other side of the shrine, near the wall with the candles, performance drops well below what is expected.
Reducing foliage visibility to High seems to eliminate the problem, although FPS only increase from 55-58. Other settings make no difference. Actually, turning off vsync also 'resolves' the issue, but that's less than ideal, major caveats and causes more 'stuttering' issues than it fixes.
When moving back a bit from the dynamic lights, the scene stops stuttering, with a minimal 2-3 FPS increase. RX 6600 XT, i7-11700k, 16GB, SSD.