That's the reason he gives for people initially going into CS, but he says that, once they get there, they tend to really enjoy the material. Apparently it wasn't so in the dot com bubble; people freely admitted to hating the material.
That is, before when kids showed up to get rich, they struggled through the advanced math and hated it. Now when kids show up to get rich, they expect the advanced math, but see easier/more-engaging routes through things like web, UX or media spurs.