Radio wasn’t as strictly partitioned by demographics. On your basic AM top-40 station in 1968 you’d be likely to hear the Supremes, Beatles, Sam & Dave, Monkees, ? and the Mysterians, Aretha Franklin, “Love is Blue” and the 1910 Fruitgum Company, back to back.
It probably says something about today’s entertainment as a packaged commodity, but I haven’t thought that through.