If I'm SquirtyBoy on PornoTron, I still have to convert BitCoin/Ethereum/Whatever into cash so my landlord doesn't kick me out onto the street.
(Unless you mean consumers should be paying PornoTron in cryptocurrency, which PornoTron then exchanges into fiat currency, and then pays SquirtyBoys in that. I think I mistook what you meant by "middle men" - I thought you meant things like PornTube, whereas you apparently meant Stripe/Paypal/etc.)
See the article for what I mean by middlemen. Stripe/Paypal are not middlemen for adult entertainment companies.