Pornhub already runs a marketplace. You can send money to a "verified" model through the site. The main difference between pornhub and Backpage is that pornhub

Pornhub already runs a marketplace. You can send money to a "verified" model through the site. The main difference between pornhub and Backpage is that pornhub is for videos but Backpage was for live meetups (Backpage facilitated the sexual acts; pornhub only monetizes them).