(Obviously, this post is not aimed at you, Dissident, but written to the sort of people you're arguing against)
"This forces them to overlook the abuse that most often goes on behind those closed doors, sealed off from the rest of the community, and to externalize the threat onto adults who exist outside of the home."
I know that most people in this culture think that one of the most horrifying things kids could be exposed to is material (if not activities) of a sexual nature. This is a blatantly sex-negative perspective, but it's not the only perspective possible.
Is sex really that horrible? Is it worse than kids getting a hold of cigarettes or alcohol or other chemicals that could stunt their growth? Or even kill them! Or being exposed to their harmful side effects (e.g., second hand smoke, abusive alcoholics)?
Despite the fact that sex is a natural element of life - and no, maybe prepubescents are not designed for procreation, but the journey of sexual awakening is a long one, and the longer you hold off the departure, the more you're stunting that development.
Is it really worse for a kid to be appraised of the details of the timeless dance of pleasure and immortality, than to be exposed daily to fictional depictions of bloody violence - essentially, the art of snuffing out life for usually petty or downright unwholesome justifications?
Of all the things kids can and are inevitably exposed to in their lives, seriously, what makes sex so uniquely bad? Sex isn't designed to hurt and traumatize people. It isn't designed to ruin people's lives. It's designed to make people feel good, and to fulfill some of their most basic psychological needs and desires.
If we've developed a social culture around sex that is dangerous and potentially harmful to kids, we need to own up to that. It's not the way sex has to be. Is your imagination so limited, that you cannot envision a version of sexual pleasure and satisfaction that is wholesome and appropriate even for kids?
That's your problem. Your brain is limited to the world you see around you. People like you will never change anything in society for the better. So why don't you step out of the way, with all your cognitive limitations, and let us gifted visionaries do the work we need to do to make this world a better place. For everyone.