Let's investigate that claim. Does OF physically and emotionally abuse its creators? Does it perpetuate human trafficking? Does OF create drug addiction and use that to control its creators? Does OF force its creators to have sexual contact with potentially violent or diseased/depraved individuals?
Ask yourself, would you prefer your family members to be under an IRL pimp or run their own OF?
If you look at this realistically, OF is not nearly as morally reprehensible as an IRL pimp.
If you'd do that for your children, why not regulate the free market and save everyone's children from the obvious and predictable harm that you can see your ideology leads to?
(if your ideology leads to very predictable harm to children which you need to intervene protect your children from, maybe your ideology sucks).
Unless you plan on keeping your kids on a leash 24/7, best you can hope for is they won't get curious and their friends won't pressure them into it.
There's a reason regulation exists, it's to stop morally bankrupt people from exploiting people. Unfortunately it doesn't go far enough, like with the existence of OF.