It would be rather trivial (if not constructive) to make a throw away account, submit something, and upvote it. It'd be pretty easy to correlate any upvote with an a personal upvote (not to mention how easy it would be to "disprove" that upvotes worked: no change on reload) ?

I'd argue this whole shadow ban idea is a bit of a dead end, and it should just list this stuff on the profile page or something.