Genres I don't like and probably will never like:
Hair metal. This music fucking sucks and anyone who ever liked it must be braindead or incapable of detecting any kind of subtlety.
Old R&B/Motown shit. Not as offensive as hair metal but the music isn't really about anything and the arrangements aren't very interesting.
Folk. Theoretically this music could be about anything, but the artists usually confine themselves to the trappings of the genre and write songs about women or walking around in a field. It's not that interesting lyrically or instrumentally, with the same boring acoustic guitar and rustic-sounding fiddle.
Most metal. People cum in their pants talking about how metal is all intellectual, the most sophisticated genre since classical music. I feel like I'm the only one that sees right through this genre. It's like the gritty Christopher Nolan reboot of musical genres. There's no real poetry in it at all.
Rock has some good stuff in it, though. Some great stuff. Provided it has a strong foundation in melody and a conceptual framework that doesn't come from stupidity. Not a big fan of most progressive rock; it doesn't know what it's trying to do. Obviously what people find interesting in a musical structure is entirely subjective. But I don't find long guitar solos to be that interesting. The guitar isn't really an instrument that lends itself to extended or sophisticated solos.
Classical and jazz have some really, really great stuff, but the inherent elitism that these genres attract makes things painful at times. Classical could use some injection of that "rock 'n' roll" spirit, some added spirituality and recklessness in performance, rather than the cold academia that largely defines the contemporary era. It's a genre that grew more restrained with time, whereas rock grew less restrained. But a beautifully played composition in this genre often says far more than some overwrought prog rock album.
Music is about the music, the arrangement and the performance. The lyrics are really not that important, which is why although I can respect a figure like Bob Dylan, I rarely embrace his music. And hey, video game music is great, too. It does some great things instrumentally. Just the other day I was listening to the Final Fantasy VII soundtrack, a "war horse" of that genre. Very moving listening at times.