And when that happens, then you can come back and tell us "I told you so." Until then, you're just another fearmonger yelling that the sky is falling.
My prediction... it's never going to happen. And I'm willing to put my money on it.
Reality check:
It already has happened with homosexual sex. It is beginning to happen now with pedophilia.
I suggest you start looking for a second job, because you have a lot of money to be paying out.
Consider prostitution. Many years ago the rationale for making prostitution a crime was that it was considered that the wife and children of the man engaging the services of the prostitute were victims in that funds used to support them were reduced and family ties were disrupted. This is still true, however, no court would consider family members victims today.
All that is necessary for the court to give approval for such things as sex with minors is to diminish the status of the minor. It is similar to abortion. Once society was taught to consider the fetus as something less than living human being abortion became legal, then accepted, and now preferred in many circles.