Give it time. It's about age demographics, not about music.
In the "classic era" of the 60s and 70s you could find "good time oldies"/"golden oldies" stations on the air. You could even find "adult contemporary" stations that played Sinatra and big band music through the 1970s and into the 1980s.
The "classic rock" stations have moved from playing "60s & 70s" to "60s, 70s, & 80s" to "70s and 80s".
I’m not sure. The 50’s and 60’s still get a lot of play and I notice the young kids around 16-24 know all of the songs. Same with 70’s.
I work part time at a small pizza joint and all the kids there, mostly 16-17, prefer the 70’s to the late 80’s or 90’s. Maybe it’s they were raised right! lol