I think its an issue of wording. Saying "I don't like black belts because they smell funny" or "A black belt would lose in a fight to a dirty sock" is mild, and generally humorous. None of said quotes have ever sparked a hostile response. Criticism without evidence doesn't have to be offensive. If the tone of the post is confrontational, that could be a problem - like the example post of The Man and Bahamut. It's clearly intended to spark flaming. I don't think all oppinion posts, positive or negative, should be labelled as spam. They can be just as pointful as any other post. And of course, like any other post, they aren't allowed to be blatantly offensive anyway.
