Personally I like quite a lot of vtuber music I've heard, but I get why it's harder to get into it. The karaoke streams are mostly just dumb fun rather than serious attempts at performing which is something you'll either love or hate, and the records have a lot of production quirks that can make them sound messier than more mainstream music.
Putting on a vocal performance that will sound good on a record is a very different skill to putting on a vocal performance for a live audience on stage or in karaoke, and most vtuber talents have little experience with the former, at least to begin with - not to mention that cleaning up vocals a chick recorded with a Blue Yeti in her bedroom is a much bigger ask than cleaning up something recorded in a studio with proper acoustic treatment, doubly so if there are multiple singers who all have completely different setups. This results in most vtuber music being mostly electronic pop as it's easier to mix heavily processed and pitch-corrected vocals against electronic instrumental sounds, which isn't going to be to everyone's taste especially here since we're nearly all old gits.
I used to be a lot more opposed to this when I was younger since I grew up listening to a lot of rock and blues where the raw musical performances are the main appeal so cleaning up sub-optimal performances in post felt disingenuous and distracting, but learning about the production side of music has made me appreciate that as an art form too.