> In the US, the plan is to require adults to take a picture of their state ID and upload it to a third party that provides age verification.

That's not just the plan - that's what's already legally required in many US states.

These laws were introduced by the explicitly religious right-wing groups like Exodus Cry and Morality in Media, as ways to de facto outlaw pornography (in their own words). They've since been laundered into the mainstream so the general public is unaware of the root cause.