The quality of what got air time on the radio dropped off about then, but it's not like the world stopped producing talented composers and musicians. In fact, my favorite genre went thru a huge neo-prog resurgence in the mid-1990's into the early-2000's. Even popular radio still contained at least a few gems all through the 1990's, which have become true classics today.
I should start another thread on "new classics", or new tunes for old rockers. I think you'd be surprised how much great newer content is out there, just harder to find today than turning on your favorite radio station in 1973.