I also want to point out that the industry is based on youth as well. When you look good whether you are male and female, the porn industry will hire you.
But once you are old or lookin like you are old... opportunities dry up. Looking at Ian Scott these days is kinda sad... his now doing two bit parts on gang bangs. When way back when he used to to be the star of the show. And looking on his twitter page, he has this constant blank stares.
Another factor is drugs and alcohol abuse, This is an industry of excess! I think there is too much of everything on the sun. Again another way these people will end up washed up.
Finally most of them started young and has only one life skill and that is to fuck! And when you are OLD that's not something that's completely attractive to alot of people.
I can't blame people who got up and left the industry. I think in POV Julian Rios did it right!! When Julian saw the writting on the wall. He got up and left almost abruptly, I might add and lived a life of peace and quiet and work as regular employee, a wife and kids.