I actively seek new music (and discover older music that I previously didn't listen to, just like you described) but also have bands that I've been a fan of since I was a kid that I still listen to. I exclusively listened to 60s and 70s rock when I was growing up, Zeppelin and The Beatles are still two of my favorite bands, but I have definitely expanded my palette since then. I agree that the "music these days" take is a tired one; if your only source of new music is the hits radio, of course, it will all sound the same.
I have this beef with people who say new country music sucks (or any genre for that matter) - sure there are bro-country singers that only sing about trucks and beer, but there are also insanely talented country musicians and songwriters out there right now.