my point is that genres are necessarily exclusionary, first and foremost, because most people's "taste" is a completely arbitrary thing based off of EXCLUSION. you don't actually like metal more than emo, you've just decided that you should like metal more than emo, or rather that you should hate emo.
if one, an average "one", says "i like teh grim blakk methul", then while listening to a band that claims to play "teh grim blakk methul" that individual will make a conscious effort to convince themselves that they are enjoying the music, because they have arbitrarily decided that they are a "grim blakk methul fan" and should enjoy that "kind" of music.
same goes for the opposite, i.e. if one has decided that they hate "emo", then they will make a conscious effort not to enjoy a band that claims to play "emo".
learning to separate what you actually enjoy from all of this bullshit categorizing is the first step towards artistic enlightenment.