If people who want more variety are the majority, I suspect the problem is just that those people don't listen to radio anyway.
Like, think about how many stations are Christmas format, and how "Christmas music" is a very regimented set of about 20-40 songs from the 1950s. To paraphrase XKCD[0], radio embarks on a massive project to carefully recreate the Baby Boomers' childhoods every December[1]. Probably because they're the only ones who still even think about using radio anymore.
Next time you listen to the radio, pay attention not to the songs, but to the goods and services being advertised next to them. That will tell you everything you need to know about who is still listening to radio.
[1] don't forget.
Though it goes both ways: non-boomers are not listening because radio has nothing to offer.