There are plenty of excuses for the decline of terrestrial radio, AM in particular -- all of them valid -- but I'd put CONTENT at the top of the list, not at the bottom.
Here's what you miss: The content has nothing to do with consultants or anyone who works in radio. It has to do with the audience, and delivering that audience to advertisers. They're the ones who drive the content, and why radio sounds the way it does. Those of us who work in the industry know more today about our audience, and how to reach them, than ever before. As a result, we're doing a much better job of focusing on what the mass audience wants. Unfortunately for you, it's not what YOU want. But for everyone else, radio content is great, and is why most people aren't motivated to subscribe to Sirius or other alternatives.