That is not corporate greed. That is the reality of selling advertising.
And if anyone is to "blame" its the advertisers, not radio stations. There are just not enough ad buys for over-55 demos to sustain any format that depends solely on seniors.
...and formats like smooth jazz are blown up in favor of more and more foreign language, talk, and sports programming. FM just isn't fun any more.
Smooth Jazz was not "blown up" but, rather, declined in listening in all age groups and lost nearly all its under-55 listening so that there was no way for a commercial station to sustain the format.
And I'll bet the listeners to radio in the historical language of Tejas, and the sports fans and the talk junkies find radio to be plenty of fun.
That said - Houston FM is so horrifically bad (except HD-2 formats) that about the only non-HD-2 on my presets is 103.5 Bob-FM, which might be overlooked for the most part in Austin, but is better than almost anything on the air in Houston. So I guess that is DX.