I think this is quite relevant, but for the opposite reason that you're implying. Yes, news has always had the unreliability problem, and maybe it is especially bad today, but the corollary problem is the topic of the OP: Americans distrust the news. You claim the reason for increased distrust is the obvious one: The increased badness of the news - that reporting has gotten so incompetent and/or misleading that people are now seeing it through the Gell-Mann amnesia. My experience, however, is that more and more people are using Gell-Mann amnesia (or just general knowledge of reporting incompetence) as a blanket excuse to dismiss media that disagrees with their social/political feelings. They are clinging to this new idea that they know better than those fools reporting the news, and so they throw the baby out with the bath water to serve their preconceptions.