It's really pricey to hire game devs and it's not easy to find dev who are ready to do porn game
it's not just risks, being an indie developer means already not making a lot of money, if you then develop niche games like porn games it's really difficult to make even just enough money to live of it, to hire just 1 person full time already means to earn at least twice as much as you need for you alone
of course it's much easier to hire someone part time for only a few hours a week or to higher someone and pay them per job done but both options are still very expensive