If I ran a talk station, and knew that the history of progressive talk was a story of disaster and also knew that the centrist / moderate field was served by PBS, I'd redouble my efforts in the conservative area, knowing that "sore losers" make for long TSL.
At the risk of derailing this from the popular game show "Who's Your Favorite County Recorder?" I agree that progressive talk was a disaster. If you consider Air America to be the great experiment in making progressive radio work, then (IMO) the reason it didn't was that they failed to understand why right wing talk radio worked in the first place.
It was built from the ground up. It didn't spring fully formed with conservative hosts in all day parts. Rush built his audience over time, honed his shtick, the finished product became wildly successful after a lot of work and then - and only then - a mold upon which entirely conservative AM radio was built. Air America tried to air-drop a fully-formed progressive talk model into the market, with expensive yet unproven hosts manning multiple shifts, working the kinks out as they went along.
I also agree that "sore losers" work better than smug winners. Rush made his bones railing against Clinton in the 90s. I'm fairly well convinced that on some level, he wanted AlGore to win in 2000, so he'd have an easy target. Suddenly becoming the winning team put him in a pickle, but then something terrible happened which allowed conservative talk radio to be not just the winning team, but the cheerleaders as well. Then Obama won, and grievance politics became profitable again.
Right now? There's not as much money to be made from being the "sober voice of reason" on the radio. Advertisers keen to sell "tactical" vests, "tactical" sunglasses, and "tactical" diaper bags (seriously, this is a thing) will want to advertise their wares at "Patriot Freedom Eagle dot com" to a rapt audience on the airwaves.
KTAR could do well financially to lean into breathless reporting on Hunter Biden's laptop and Kari Lake's "brave fight for election integrity."