> the UK wishes to establish this and not want it to lead to an insane amount of privacy leaks, it should consider developing a technology that makes it work in a privacy-respecting way
They don’t care about the privacy aspect.
A key part of effective age verification is associating an identity with the account. They don’t just want to confirm that the person accessing the site has access to an ID of anyone who is 16+, they want to make an effort to associate the ID with the account. It’s the same reason why when you present an ID to buy alcohol they look at the photo to make sure the ID is actually yours, not just that you have an ID of someone older in your possession.
They don’t care about the privacy aspect.
A key part of effective age verification is associating an identity with the account. They don’t just want to confirm that the person accessing the site has access to an ID of anyone who is 16+, they want to make an effort to associate the ID with the account. It’s the same reason why when you present an ID to buy alcohol they look at the photo to make sure the ID is actually yours, not just that you have an ID of someone older in your possession.