You don't need a computer algorithm to prove that one genre is artistically better than another, just a decent taste and knowledge of music.
Oh and the only one you need to do any "proving" to is yourself. So yeah, genre appreciation is subjective, but that doesn't make all genres necessarily equal in artistic value, of course not. But I'll say it again, there is good music and bad music (and everything in between), not good genres and bad genres. It's just that some genres (due to their inherent characteristics as described by Postulate, as well as those of the people/scene generally involved etc) tend to have more crap than others. And that is not just some subjective opinion.
Having said that I'm against (seriously) mocking people based on what they listen to and stuff like that. It's immature.