I was a regular and avid talk show listener and I heard no dog whistles even when the left kept screaming about them. IMO far too many conservatives have bought into defining Trump’s supporters as conservative long term listeners when it’s simply not so. RadioE lost conservative listeners when they exchanged them for Trump supporters.
So, when you talk about talk radio listeners, there is a dividing line that started earlier but intensified right after the Romney loss in 2012 where RadioE and other formerly conservative outlets/organizations stopped promoting conservatism and started an anti-establishment GOP all out war in the name of conservatism.
From Heritage Foundation’s Washington lobbying arm, Heritage Action, to CPAC, RedState, The Blaze, Breitbart and more; *all of them* were much more concerned in promoting anyone who attacked the GOP as not being conservative enough. Including Trump.