I understand economist Kartik Athreya's frustration, in that it's hard to have a rational discussion when so many voices are profoundly stupid. I remember once teaching a class on International Finance (grad school students could be 'instructors' in their 4th plus year). I tried, a couple times, taking a subject and letting the class discussion grow endogenously: what do you think of the currency crisis (this being 1992), or the Fed? It didn't take long for the most voluble speakers to monopolize the debate, and unfortunately they were wrong on so many dimensions it always became a pointless discussion within a few minutes. Confused thinking leads nowhere in particular and can be indulged indefinitely without progress.
I'm an unabashed elitist. I chose my wife because I think she's better than other women, evaluate wines, books, investments, new hires, all on an ordinal scale from bad to great. This is often confused with racism or other repugnant thoughts because such discrimination tends to disproportionately affect socially disadvantaged groups, but that's incidental. Economists are generally very Liberal, but they also obsess over how smart various economists are, closet IQ idolaters. The key is moderation in all things. Most signals of quality are not linear, so you have to not focus too much on one dimension of someone or something.
The problem is, where to draw the line on who's qualified to voice an opinion. Now, the line must be related to some obective credential. Unfortunately, having a degree in economics is not very impressive, because so much economics is irrelevant or wrong (based on bad assumptions--the logic from assumption to conclusion is usually right). That is, say you really understand Debreu's Theory of Value, or Stokey and Lucas's Recursive Methods in Economics. That may get you tenure, but those books are only related to economics in theory, not practice. Further, as a PhD, you can't draw the line right beneath your credential, but rather have to choose something like an undergraduate degree--otherwise it seems too self serving.
It would be helpful to have some metric of analytical competence to keep the discussion, at the least, logical, but it's hard to think of one that would not exclude too many thoughtful, energetic people. Any exclusive club tends to corrupt itself, and develop insular, self-serving logic.
So, I sympathize with his point--there's too much crappy economics out there--but unfortunately, a PhD is too noisy a signal. I don't have a solution.