If you click on a username, either while searching or while downloading, you could browse everything Napster had indexed. If people didn’t configure Napster right, you could browse their whole C:\ drive. Good times.
Admittedly, what I like about Spotify is how easy it is to share music with other people and discover music from my friends just by looking at their profiles or what they're currently listening to.
There are even certain livestreamers I follow specifically for their taste in the music that they play in the background.
It was a great way to discover new music.
FWIW, someone I met doing random AOL profile searches in the mid-'90s and I are still online friends. We both liked the Dave Matthews Band and played varsity tennis, and this met my minimum chat requirements. Now we are both former journalists working online, dealing with bipolar disorder and the recent death of a parent. The internet might be weird sometimes, but that (and a random story of getting a web development job because someone had the wrong email address for the person they were actually trying to hire) will always go down in my "Internet wins" column.
FWIW, I have a couple friends like that. We bonded over some musical interests of our teens and occasionally check in on each other although most never met in real life. Maybe that’s still happening in game chat? But I can’t imagine something like yahoo chatrooms still exists.