Exactly. wedrifid's claim appears to be that chaosmosis saying that without being downvoted heavily means that other members of the community have not yet rebuked him, which is evidence that he does not deserve rebuke.

Certainly.

Another function of wedrifid noting that explicitly is to remind people to downvote if they see something that should be rebuked- if the community is failing to downvote bad material, that is cause for shock and confusion.

I suppose that connotation does come across but I wouldn't necessarily want to say that in this context. I would estimate that I am more inclined than average to support the use of such a response. I wouldn't outright encourage the specific language but it certainly wouldn't bother me and I would either leave it neutral or possible upvote.