Part of the answer is that such people aren’t actually listening to the music. They are getting something else out of it, like using it as background noise, or just as a beat to dance to, or as in-group signaling, or maybe access to the culture associated with the music, or perhaps they are self-medicating with it, or maybe they are ogling the performer, or perhaps it reminds them of something positive that happened when they first heard it.

None of these uses require the music to be “good”.

Actively listening to music is a somewhat rare activity.