^THIS, and the rest of your post.
Therehave been times when it has been otherwise, but that's been the exception. I'm old enough to remember more times than most people will remember.
Pre-recorded radio music was EXTREMELY homogenized until about 1956. When rock and roll took off - a good part of it coming from "low budget" recording artists and record companies - the upstart companies piled on and, by 1958, the competition was fierce and, because of so much non-formula rock and roll coming to the forefront, I consider that probably the best "pre-Beatles" year for radio. Elvis Presley was probably the biggest influence bringing rock and roll to nearly every corner of the United States and Canada, but he couldn't have pulled the entire load alone without Bo Diddley, Chuck Berry, etc. (Actually 1957 was probably the very best of all rock and roll years ever, but it took radio a year to catch up...)
By 1959, big money was getting into rock and roll...and the really fast and hard stuff was somewhat pushed back. Big-money interests have always tended to be conservative (going back much farther than my lifetime), and it showed in the music that was trending. By the end of 1960, ballads and slower stuff were back to near-dominance, though the traditional adult pop standards, often with big band overtones, no longer dominated. But, often, the most popular songs became ballads or, sometimes, lush pop instrumentals. (think "Theme From a Summer Place" the #1 song of 1960.) Even with radio music again somewhat homogenized, other rock and roll and independent stuff wasn't kept entirely at bay, because hard-and-fast "formatting" still barely existed. The homogenous music period on radio didn't involve much more than 1960 and parts of 1959, because new styles were coming out at a lightning pace once 1961 arrived, and some juggernauts (such as Phil Spector, "The Twist," and Motown) were soon to break wide open, or already had. Rock and roll had a very bright and lively feeling to it, with the teenage ballads, the girl groups, the first soul music, oodles of rockin' instrumentals slongside the juggernauts. Generally the music was all about having fun...
Then came The Beatles.
Independent music had a good chance being heard on the radio around 1958 and first-half of 1959, then a lot more independent stuff started showing up around 1961 (after that "valley" in 1960), and the period 1964 to 1968 was just "crazy" with it. (A good indicator is that there were more songs that reached the Billboard Hot 100 in 1966, than in any other year ever. More successful titles = more churn.) Music started to homogenize again bvy 1969 and 1970, and stayed thus for a decade, though the last half of that was a change in the dominant music when disco became huge.
The last time I'm aware of when alternate types of music had a chance on the radio was around 1981 to 1983, when New Wave and other alternative forms became successful. But, now, it is thirty years since I've noticed much independent music on the radio. Of course it's hard to know when, nowadays, it seems that absolutely no current song ever played on any American radio station will ever be announced or identified.
I have not enjoyed radio in thirty years, because of that.
Hugs. Trust me, I'm so right there with you on doctors.
