If someone is ready to pay bitcoins for porn then it might be a good fit together since bitcoin offers a good privacy level, I remember po--.com used to accept bitcoin but I think they stopped using it after they had processing issues or due to low demand.
Now lot people prefer to pay with bitcoin as it is anonymous to certain extent. Even now and then the price difference will give additional profit if payment is made through bitcoin.
But I do not think those models will get benefits from bitcoin value appreciation by saving some bitcoins for longer periods. They might be rushing to cash out bitcoins unless they are educated about bitcoin investment opportunities.