You suppose we consider it immoral? Do you think there will be a time in the future where adults will be having sex with 5 year olds and as a people, we'd just shrug and consider it normal?
Yeah, I think its highly likely that at some point we'll discover a biological basis for pedophilia, find out that any "harm" to children is basless superstition and encourage sexual liberation in children.
And I believe this is will happen due to liberated people campaigning for the sexual rights of the child.