You can quite easily see NSScrollView jitter/stall if you open a Finder window -> Icon view -> Use Groups -> yes.
Make sure the folder you are viewing has a few collapsable sections. Collapse some of them. Then start vertically scrolling top to bottom. Scrolling will get interrupted often when the cursor moves over the collapsed sections. The scrollbar will freeze visible until you click somewhere and then the scrolling animation will start.
You might think the horizontal scrolling of the collapsed section is colliding with the vertical scrolling and that that is causing the stutter but that's not what's happening. In my testing I can just stick a subview partially outside the bounds of the document view (but not increase the width of the document view so horizontal scrolling is not enabled) and the same stutter occurs.
I went back to macOS Monterey and tried to reproduce but could not. Not sure when this bug came about. But adjusting the scroll point in a -scrollWheel: override without calling super avoids the issue and scrolling seems much more responsive. I think just calling -scrollPoint: kicks off Core Animation implicit animations(?) they seem to do a good enough job.