Every idea is a "frat-boy idea" until it succeeds. Ignoring the naysayers is one of the necessities for being successful (I think, from my unsuccessful perspective...).
Even though I had none of the ideas he mentioned, reading this article gives me a strange urge to start a business in each of these categories, just to prove him wrong.
Well, there's a lot of value in appreciating how your predecessors have failed. I think his objection is not so much against the list of ideas, but rather people who ignore the mountain of failed attempts in the same field, who seem to believe that they're magically different, and somehow destined to succeed despite the sheer number of failures in the past.
