I have used it a few times in cases where I am showing some text whose size will vary a bit, around the scrolling threshold. Better to consistently show the scrollbar than have everything jump.
Still surprised that you are so worked up by this - is it really so common or so problematic?
>>stevag+(OP)
I encounter inappropriate `overflow: scroll` that should have been `overflow: auto` very frequently (in the scheme of things), probably averaging over once a month.
Your use case sounds like it might be better handled by `scrollbar-gutter: stable`, though I might adjust my judgement on seeing it.