A theory came to mind: with Trump's ascension to office, there will be less reason, or even no reason, for his fans to listen to talk radio, i.e. mainly AM radio, because they'll get plenty of reinforcement from mainstream media, either in course of the usual coverage of a president or because some media owners have fallen into sycophancy. In any event, there'll be no need for talk show hosts to amplify the extreme-right platform: it's going to come right out of the government. Those hosts have thrived in opposition; now they'll have nothing to rail against.
This theory may be nonsense but I believe it's worth thinking about, at least.