I always took that with a grain of salt aimed at the eye of Power Players.
Much like the superb book "Listen Up, You Primitive Screwheads" by Mike Pondsmith, for CP2020 (but is useful for any newb-to-mid-tier GM).
But given his attitude, you're probably more correct he's just an opinionated dick. I won't hold that against him, of course. But you know, the Internet Tough Guy videos are pretty cringetastic.