These celebrities have the money but don’t have the interest to buy a radio station. There is no shortage of New Jersey or New York-based rock musicians who could have bought WPLJ when Cumulus wanted out in 2019.Anyone can buy a radio station. It doesn't have to be a big corporation. Stevie Wonder owns a radio station in LA. Imagine if a musician from Detroit bought a radio station. How good would that be? I bet the sale price here is less than $8 million. Berry Gordy spends more than that on his landscaping. That's how easy it would be to improve the quality of radio.
I’d be surprised if it didn’t have to do with the chances of not having a return on investment, competing against larger clusters with economies of scale and considerably more resources, let alone the challenges stand-alones have just trying to break even. Stevie Wonder has owned KJLH for decades largely because he wants to for the community; KJLH’s performances with ratings and revenue is almost immaterial.
One minor aside, James Brown was part of a group that owned WJBE in Knoxville TN but financial problems forced the station’s sale a decade later.