I dunno, I feel like porn is one area where society in general really does care about their privacy. People who don't care about most tracking will still use private browsing to watch porn, and companies go to great lengths to highlight their discreet billing/packaging etc.

One doesn't really exclude the other. What you wrote is true, but people primarily care about not being discovered by people they know, and cloud is a go-to business model for people too lazy to invent something that's sustainable and actually beneficial to the user... Given how hard it is to monetize causal porn browsing, I wouldn't be surprised if some companies started giving in to the temptation...