it all sells. Content purchasing is an investment that can pay off for a long time.
The self shot is a new niche and probably a fad.
The ex gf stuff is what people use to call Amateur or Home Town.
So the people who bought this stuff 5 years and 10 years that had good quality pics in these niches can still use them
I however dont think people will still be able to use self shot in the same manner especially in regards to a legal standpoint.