I'm an older Zoomer and this was never the case for radio in my lifetime [1]. I heard "college radio stations" being a bastion of this but I've never listened to one myself.
One of the earliest internet services I remember loving was Pandora because it recommended me artists I never heard on the radio and was the start of my love of music.
[1] I'm guessing it was related to all radio stations being owned by the same companies.