The numbers appear to tell a different story than what you suggest.
On 1 million impressions I will make around 30 sales at least on average. On 1 million impressions from tubes such as Pornhub from what I gather it's common to make 1-3 sales on a pay site.
There are only so many potential customers out there. You say that they are bringing it to more people but that doesn't make much sense. Why would they not have been able to find porn before simply by typing a few keywords into Google? For the most part it's the same pool of people we would have had before anyway.
Now let's say there are 500 million potential qualified customers out there which we will simplify to one impression each to make this easier. Do a little math.
A) 500,000,000 / 1,000,000 impressions * 30 sales = 1,500 sales
B) 500,000,000 / 1,000,000 impressions * 3 sales = 150 sales
Where would you prefer to send your surfers to to make the most money. A or B?
And again PornHub isn't going from rural village to rural village hooking people up to the internet, handing them a business card, and telling them "The internet is loaded with porn, you should try it sometime. Come to PornHub.com!" with a wink.
Almost all of these people would already know there is porn on the internet and would know to use a search engine. Fabian isn't a magician who can magically make new porn surfers appear out of thin air. These surfers were already there. Think about it for a bit.