That's why I'm talking about an “Id card” using Zero-knowledge proofs in a cryptographic chip, not using a paper ID with your picture on top…
You still need to send a digital image from the id, signed by an authority, saying "this person is 18"
You then still need a trusted ID service or algorithm to capture an image of the user _at the time of use_ to compare that to.
Just having access to your digital ID credentials proves nothing
The zero knowledge proof only helps prevent tracking between the ID service and the website you're logging into. This is valuable but requires standardisation and client side support, which doesn't exist.
All the time the client side is implemented by JavaScript served from the server side you're just trusting these parties to behave and not snoop
> You then still need a trusted ID service or algorithm to capture an image of the user _at the time of use_ to compare that to.
> Just having access to your digital ID credentials proves nothing
If I have access to your digital ID I shouldn't be able to impersonate you anymore than I should be able to fly using your passport.
Your passport is useful not just because it's difficult to forge, but because border control is a thing.