Well, i personally dont watch e-sports, usually because i would ratger play them(Though i have already watched one or two and really enjoyed them).But saying that people who watch them are, putting in few words, stupid is completely ignorant.Its the same as saying that someone who watches football instead of playing it is a moron.There is simply no logic.People like to see professional players play, because they play better, which in turn make the game session much more exciting, and people like to cheer, see someone they respect win.Its the same reason as any other sport.
I know that great part of a joke comes from making fun of other things, in this case of lets play or game streaming, but his insistence on this and his constant flamming and ignorance in this matter just makes him look ignorant and stupid, not funny.