I am ignorant of what it means to repost art. Is Danbooru in violation of an artist's request by having it here, or is this about other artists posting their work as if it were theirs(plagiarism)?
Artists who want their artwork banned from this site need to contact the admin directly, either via email or the provided DMCA form. Any "request" that doesn't follow proper procedure carries about as much weight as wet tissue.
As for the reason you were downvoted, it probably has something to do with the fact that you bumped a two-year-old post to ask a question that has been answered on the forum many times already.