yeah- most people who have crappy taste in music reflect it in their personality, honestly.
for example most guys who enjoy 2 and a half men will have a crappy taste in music, usually very RnB and mainstream influenced (I'd imagine, and from experience), and lol noone who likes two and a half men is worth dating- you'll be able to notice the difference between the people who do and don't.
The same thing goes for girls, but thats not as apt an example, I'm sure someone can do better than me here, I don't really think its shallow at all tbh, some people just suck at these things.