Technically speaking, there's actually nothing wrong about the way this guy is dressed. He's not showing the world anything that should normally be kept private, and he's completely covered. This is a lot less offensive than seeing someone walking around with their bottom hanging out of their shorts or pants. Nevertheless, it's still a bold fashion statement which we don't expect to see replicated by a major fashion house any time soon.
This whole 'wear your pants low' trend started in rap music around twenty years ago, but it's being stepped up a gear here. Normally, wearing them low just means that they're a couple of inches below the waistline. He's decided that it's fine to wear shorts below your entire butt, so long as your butt is covered up by your wifebeater. One question though; how is he managing to keep the wifebeater in place like that? Is it actually more like a tunic?