The issue is trying to use genres as specifically as possible instead of being a broad category that covers a wide range of music.
Metal is the worst for this. The vast, vast majority of people would call everything from Black Sabbath to Metallica to Pantera to Death to Behemoth "metal", but the genre snobs need to differentiate it all for some reason.
Yet, we're perfectly okay to call everything from Blue Oyster Cult to Fleetwood Mac to Nickleback "rock".
I agree with your general point about metal subgenres but they do help me a bit. For example, I've got no disrespect towards the subgenres of nu-metal or the trve cvlt type of black metal but it's just not for me, so if I see something tagged as that I can easily avoid it. As I say, that is in no way a diss of those genres, they're just not to my taste.
I love metal, but maaaaan fans take subgenres too seriously. I once saw a bar fight in my very peaceful city where one guy was shouting "That's not sludge metal! That's stoner metal! You don't even know what sludge metal is!"
And I find myself doing that shit, too. I was talking to a buddy a little bit ago and realized that I had just said "I'm currently listening to a German symphonic folk metal band, but the vocals are pure black metal."
Thats extreeme metal elitism, but you also prooved the usefulness of genres. How else, without using genres, would you describe that german band as efficiently as you did so someone like me can understand it and say:
Specific genres are awesome to find new bands, that you like, because they sound similar. If I like power metal and you recommend me Behemoth, because I like metal, your suggestion has no value for me, while I probably would like another power metal band like Blind Guardian.
Maybe this is a modern thing with streaming that holds some weight - I wouldn’t really know as I don’t use the streaming services too much. I can say that as an old electronic music fan/DJ, genre and sub-genre won’t be leaving that scene anytime soon. Probably a different, unrelated conversation altogether.
These days I generally only listen to Alt Rock but that is still a broad category from it's start in the early 80s to today. Under Alt Rock falls New Wave, Punk, Post Punk, Grunge, Ska, Emo, and even College or Idie Rock.
I personally find it the most creative, expansive and enjoyable genre for music.
I am an older millennial who grew up around Gen X kids older than me.
All those Gen X kids were so fucking stuck up about music and would be so fucking rude and mean if you listened to the "wrong" music.
Guess what you Gen X chucklefucks, your music didn't change the world and more than half of you grew up to be conservatives. Why the living fuck would I give a shit about your worthless fucking opinions on music?
It took me years of growing out of the brow beating about music to understand I truly do love all kinds of music and to not limit myself by genre.
Hot takes: Nirvana is overrated, nobody even remembers Stone Temple Pilots or Janes Addiction because they were fucking forgettable mid-tier trash. People whose tastes in music never grew and still only listen to what they listened to in high school probably never grew in a lot of other ways, too.