All certificates are cryptographically linked to an identity-anchor certificate, meaning buying a certificate would require the seller reveal the private key tied to the identity-anchor certificate, a tall order I would argue.
In the case of stolen identity certificates, they can be revoked thus making their illegitimate utility limited.
Why would your design prevent that?
We have laws against kids buying alcohol, even though kids can (and do) try to get adults to buy them booze, but I don't think that's a good reason to say we shouldn't have laws against kids drinking.
If it can't, it's no better than a button that says "I'm 18"
Any number of entities can be certificate issuers, as long as they can be deemed sufficiently trustworthy. Schools, places of worship, police, notary, employers...they can all play the role of trust anchor.
how do you handle revocation when people inevitably start certifying false information?
say if an anchor has issued tens of thousands of legitimate ids, and also ten to career fraudsters who gave them a $1000
as you've outsourced the trust you have no idea which are legitimate, and if you revoke the lot you're going to have a lot of refunds to issue
(ultimately this is why countries only allow people who can be banned from their profession to certify documents)
So if say a UPS store is issued a cert and they go rogue, we can just revoke the trust anchor cert that was issued to the store, all certs issued further down are also automatically revoked...the revocation check is done either in the app or in the case of a third-party performing the verification they will recognize that there is a cert on the issuing chain that is revoked and reject the cert.
This is how TLS certs are handled too, if a CA goes rogue, all certs issued by that CA are revoked once the CA's root cert is revoked.
As for refund issues, that's a problem for the cert issuer to deal with.
no, it's your problem, as it's your brand slapped over everything, and now you've got tens of thousands of innocent people angry that you've revoked the IDs they paid for in good faith
this would translate into lawsuits, against you
But outside of this if someone is determined they can issue fake documents at this level of provenance.
Drivers licenses for example you can buy the printing machine and blanks (illegally) so you actually need to check the registrar in that location.
https://news.ycombinator.com/item?id=40298552#40298804
Talking about it or explaining it is like pulling teeth; generally just a thorough misunderstanding of the notion....even though cryptographic certificates make the modern internet possible.