One thing I've seen discussed that throws a wrinkle in all of this is the question of whether or not a parent can have control over what their kid can see when they're at a friend's house, and if the answer is no, does that mean something more global like mandatory age verification is necessary to ensure they are still protected.

The argument I've seen goes that even if a parent has complete control over what is available on their home network and on their children's devices, the fact that another parent in their children's friend group does not enforce the same means in practice the amount of control a parent can exert on this problem is effectively zero and a higher-level approach to eradicate this loophole is necessary.

I don't think I agree with that, but that's the strongest case I've come across for implementing such policies.

What I think it really calls for though is a solution in the space of community and communication rather than direct governmental intervention.