In many (most) places incest is illegal, hence "incest porn" if actually played out by family members would be illegal. Hence it's likely mostly fake.
99% of porn is fake. There are "hidden cameras", teen porn where the girls are >20, but good makeup, clothes and stage i.e. child's room makes your imagination add the rest.
OP probably thinks that the good old plumber and pizza boy videos are also real.
I don't know anyone who would try to claim they haven't watched porn, but there's a long way from doing something occasionally and addiction. For instance, I drink coffee every day, but I'm not addicted to it, just like I'm not addicted to this forum or using a computer, even though I do both these things quite often.
Get real OP.