"Otaku" does not precisely mean "nerd". It's a bit more negative, with stronger implications of unhealthy obsession, childishness, and social maladjustment.

Otaku also often sperg out about a particular thing -- trains, boats, cars. Miyazaki spergs out about planes, as you can see here.

To be fair to the guy, though, the biggest thing he criticizes about otaku culture is its detachment from reality -- He cites the movements of the characters in anime as feeling too abstract, too odd, and that they wouldn't have this problem if they just got out of the house and watched people. Basically, he says that modern anime lacks the human element -- he's definitely not hypocritical in that respect; if Miyazaki movies are wanting in anything, it's not the human element.

With English subtitles?