I have no clue how common adblock is among YouTube users, but there's probably a bigger chunk of pornhub viewers on mobile.

Pornhub is also in an unique place, given a lot of advertisers won't advertise there. Pushing prices down, but simultaneously a different set of advertisers can only advertise there. Pushing the price up. I have absolutely no clue whether or not pornhub charge more per ad view than Google ad services on average