I expect there's much more going on than just mouse path detection but I can imagine that this is already tricky for touchscreens and for people using non-traditional mouse inputs (the thinkpad nub comes to mind - but it would also be bad optics to accidentally block people using accessibility mouse tools as bot users, though then this becomes a loophole for agentic browsing!)
In general though I think this is almost definitely a good thing to reduce agentic bot abuse & spam.