What argument?
You're the one that needs to argue the presence of harm, given you're the one arguing we need to create a surveillance dragnet to shield certain age groups of humans from witnessing how their species procreates.
The default state is that humans procreate via sexual reproduction. You need to argue why we need to take action to hide this, especially given we let children witness other far more brutal activities from the human species like violence.
The argument I am asking him to make is the one about how age verification is "much worse" than "allowing children to watch porn".
If your argument in favor of that is that watching porn isn't harmful to children, then I don't understand what all that superfluous waffling about china is doing in there.
> This is arguably much worse
Surely someone claiming it's arguable should be willing to make that argument.
For me it's not that it's reproduction. Film that shows sex is not an issue as I see it and I don't know anyone that has developed serious addictions to sex in Hollywood film. However I know several people, family members included, that have absolutely obliterated their childhoods and early adult years by becoming addicted to porn. They were groomed by adults online from a young age and, although their parents tried to stop it, kids are sneakier and they got around it, exposing themselves to some truly dark things. It is not easy for families to recover from having dealt with a child with serious addiction issues.
I think it's pretty silly to argue that systemic protections are ineffective and overreach whereas the efforts of one or two parents should be enough and are the correct level of enforcement for the protection of children. The parents of the people I know went to extremes to protect their children and they were mostly unsuccessful.