My take is someone writing this sort of automation is sick of spending hours each day doing the bans manually
What sort of false positive are you worried about when it only bans people whose only interaction has been negative? Regulars have upvoted stuff if they like the community.
Do you ever visit a community and down vote the first thing you see and intend to return?
One in that list has 5 or so members and attracts about -20 votes on every post and comment. It's unpleasant to visit a community where every post and comment is at -15, even if they're "imaginary points" it makes the community hard to sort
Since Jet started enforcing the "no mass down voting" rule automatically things sit at 0 to +5.