The author comes across as ignorant at best, but then to present his own work as the Realism Hypothesis of Hertzmann, it leans more towards arrogance.
Another time I had an older PhD moved to my area (outside his) where we were trying to meet a number of objectives. He said in a meeting that "it is mathematicaly impossible" to achieve one of our performance goals. I quietly went back to the lab and ran my new control algorithm and documented hitting that goal. Never refuted him, just filed the incident away in my head.
Edit: People being arrogant or know-it-all is probably not especially correlated with having obtained a PhD, but more with overall frame of mind, and I find this comment to be a uselessly negative ad-hominem.
That's not to say it's a perfect correlation. I know plenty of people with PhDs who don't have the problem in the XKCD cartoon. But I too am careful hiring PhDs in tech jobs. Professional work is just very different than academic work. It takes time to learn it for people whose main focus is the theory. After all, "In theory, theory and practice are the same. But in practice..."
My favorited comments on this site are mostly this phenomenon. It’s annoying because there’s a built in default assumption that one is such a great thinker there’s no need to waste time seeing if an expert has already solved the problem. One of my favorite examples is the software engineer that spent significant time testing his shower mixer valve and writing a “manifesto”[1] on how to make a better one. A few minutes of googling would lead him to realize why a mixer valve might have such a wide range (inlet temperatures and pressures are not a given) and also to the actual, existing solution (thermostatic mixing valve).