That's not correct. With a government issued signed digital ID cryptographically bound to a hardware security module you can use a zero-knowledge proof based protocol to prove to any third party site that (1) you have a signed government ID, (2) you have the hardware security module that it was bound to when the government issued it to you, and (3) the date of birth field on that ID says you are older than the site's age threshold.

This reveals no other information to the site.

The EU is on track to deploy such a system by the end of 2026. They are currently doing field testing involving thousands of users.