While those users are creating and posting dog porn they are of low value to me. They're creating noise not signal; consuming resources; and creating negative brand associations. By asking them to take their dog porn elsewhere I risk losing them altogether (which currently isn't much loss) or they start posting other content.
"They shouldn't be posting X because I don't like X" sounds extremely entitled to me.
"They are damaging the brand value of the site" which has nothing to do with you. When I criticise Apple (and you use Apple products), there is no need to take it personally.
A company is free to care about users who want dog porn. That company should not be surprised when other users, or advertisers, steer clear of that company or its brand.
