The purpose of listening to music is to relax. If you think old songs are more attractive and sound intoxicating, then you don't have to listen to some songs you don't like in order to force yourself to appear gregarious.
No one stipulates what kind of songs you should listen to at any age. I am also a post-90s generation, and I like listening to old songs very much. When friends say I am old-fashioned, I will tell them where the charm of old songs lies, and some friends listen to old songs under my recommendation. If your friends really don't like old songs, you don't have to. You can keep your hobby. Many post-90s people love to listen to old songs. I hope you can meet a post-90s friend who also loves listening to old songs and share them with them.
Hope to adopt, thank you ~