Not really, Pornhub was launched in 2007, at that time they were not that many other prominent tube sites, Youporn had been around for a bit longer but Brazzers

Not really, Pornhub was launched in 2007, at that time they were not that many other prominent tube sites, Youporn had been around for a bit longer but Brazzers was pretty much printing cash at that point and growing insanely fast. They did not do it to reply to the competition and revenue was sure as hell not suffering, they did it because it was the future and they saw it as such as well as a great way for them to funnel sign ups to Brazzers and other paysites such as Moviebox. By then they were already a dominant force in the market and moved on to acquire most other tube sites to apply the same model as they did on Pornhub. Also last time I heard advertisement on tube site were still the main revenue stream for them, might have changed now as I've been out for a few years. Source: Was Lead Developer on Pornhub and Back end dev on Brazzers before that.