Not liking generic things is something that can be taken to a reasonable extent, such as not liking incredibly boring food, or music, or clothes. It's fair to not like a band because it bores you. It's not fair to automatically dismiss everything that uses certain chord progressions and to immediately think less of the musicians that made it- that just makes you a dick.

If you don't like food because it's generic as opposed to not liking the taste, you're an ass. If you don't like a hoodie because a million other people do, you're an ass. If you don't like a car because it's boring, fine, but thinking that your taste in cars is better because you'd rather have something else makes you an ass. If you prefer private schools because not as many people go to them instead of because many private schools have higher standards of education, you're an idiot. If you want a house over an apartment because you need the extra space or having a house appeals to you more, fine, but if you want it because your friends all have apartments, you're fucking retarded.

TL;DR: You're a fucktard.