I think that the improved version of age verification is to ask the yes/no question to a government third party based on a signed payload that your local device offers the service. The government already has your identifying data, they only need to certify on behalf of which person the question is asked.
Which a) has a whole host of other concerns associated with it, and b) still does not solve that problem, because it's not at all hard for a child (especially a teenager!) to sneak their parent's ID, use it to authenticate for a service, then put it back.
After all, are most services going to require the ID to be present for every session? Or are they going to require a one-time authentication for the account?
I mean most mobile devices have already accepted closed ROMs in their baseband and all/most browsers that try to interact with streaming sits require Widevine . As longas its going to hapen one way or another better it be local , and not a gov thing or a monopoly.
At the end of the day the tool should be there enforcement down to the relevant local authorities or not.
1) It is vulnerable to modifications and hacks on the local device that get it to send back a "yes" result without actually verifying anything
OR
2) It requires the device to use some kind of closed, proprietary system that allows the service to guarantee that #1 cannot happen
Now, in general, the tech world is pretty happy to accept #2, but many of the people around here would object to it on very reasonable grounds.