While I agree with you on the parts about Marrone being thin skinned, I disagree with you on the parts about the Media.
What you are ignoring is the fact that radio is and always will be about listeners. Listeners = audience base. Audience base = demographic to sell to advertisers. Advertisers = revenue.
You don't need to be an NFL intern to interpret the game and speak to the fans. In fact, guys like Jeremy White, Joe B, and Matthew Coller do a great job of being the intermediary between the Counter Trap, A Gap, 3 technique, X's and O's guys, and Bob from Cheektowaga who thinks Jim Kelly should come back and coach the Bills.
The technology available to everyone these days (all 22, NFL Rewind) mean that more than ever, the gap between coach speak and honest evaluations is closing.