He's right.I don't really expect Alan Moore to give a balanced view on comic books and comic adaptations since he's spent his whole career sneering at both industries whilst being a huge contributor. He seems to never have had a good word to say about the business and I certainly don't agree with his notion comics were primarily for working class children. He certainly didn't write for that audience, that's for certain.
This part is bit iffy too, particularly as you could remove all superhero films from the lists, and the remaining highest grossing movie franchises of all time are still films that are not based on reality but are fantasy stories to varying degrees. Superhero films seem to be an easy target when its clear that fantasy settings are what the masses want, whether its Star Wars or Harry Potter or Game of Thrones or men is capes and tights fighting baddies. The desire for fantasy and science fiction has been rife for decades.
There's only a small amount of superhero films I even like, but it's clear why people do like them. You don't have to like them I don't know why it needs to be dumped on to the point where they're deemed as not even being legitimate to the medium.