If a Moderator thinks a post should be edited or deleted, IMO, (and it's what I did when being Admin/Mod on a couple of sites) they should message the poster, explaining why they believe it should be amended, for instance, the post opens both the poster and the site to possible lawsuits for the content. If the poster refuses to delete/edit, the Mod should then take the necessary action.

Apparently PMs are not currently working so that's not an option but AF could easily post "please amend/delete because....." in a reply to the offending post.