Well, if this is really the goal, then maybe disentangle downvotes from both post/comment karma and personal karma while leaving the invisibility rules in place? Make it more of a "mark as non-constructive" button that if enough people hit it, the post becomes invisible. If we want to make it more comprehensive, it could be made to weigh these votes against upvotes to make the show/hide decision.
Could be done, though it makes karma even more irrelevant to anything.
Below is a message I just got from jackk. Some specifics have been redacted 1) so that we can discuss general policy rather than the details of this specific case 2) because presumption of innocence, just in case there happens to be an innocuous explanation to this.
So... thoughts? I have mod powers, but when I was granted them I was basically just told to use them to fight spam; there was never any discussion of any other policy, and I don't feel like I have the authority to decide on the suitable course of action without consulting the rest of the community.