If anyone writes a genre off because many of its artists aren't original, they're durab.
Nu metal is boring, skilless garbage. It all sounRAB exactly the same and the sound is terrible. It's annoying. It's repetitive in a bad way. I've never heard a nu metal song I like.
Whenever someone says "Better than The Beatles", I take it as quality wise. There's no denying the impact The Beatles had on music, and whenever someone says "I don't like The Beatles", I'm fine with it, so long as that person knows what they did and respects them.
Now, I think Van Halen and AC/DC are fucking terrible. I'd rather have a cow take a crap in my ears than listen to their music. I think they're insults to top-tier artists and should have never released an album.
Joni Mitchell and Pavement I've heard of but don't know a lot about.
Steely Dan, though, is my definite favorite band. Shit, I'm listening to them right now. Now, album-to-album, quality-wise? I'd say this is plausible. Steely Dan is probably the most consistent band in history and were always top notch, and I think that they could definitely run the table in a discussion about album quality.