>but I raise them because I think they're part of the reason (along with compliance, perhaps in some cases?) why these systems are introduced in the first place

Problem is, they are still proxies. Proxies are great at satisfying feelings, but proxies are by no means a guarantee they will reflect what they try to capture. There are no end of examples of perverse incentives showcasing how a metric can "feel" great, but end up being a big bag of nothing if not detrimental.

Other than that, even thinking along the terms of "well they must have a reason" is a great way of introducing slippery slopes all the way to extremism. I'd have a hard time arguing any answer would justify becoming more and more extremist and trying to deny people privacy and autonomy to such a degree.