> (Moving the PKI into DNS does not remove it, it just moves it around.)
Better in DNS though. You could have certs mirror the structure of DNS. Install a single root signing key for the top level DNS registry on client devices. Then you can query that to find out the signing keys for .com, .net, .au, etc. And continue from there.
One big problem with the CA system is that any CA - even the most incompetent - can sign certificates for any domain. If trust was moved to DNS, there would only be a single organisation that could forge certificates for any given domain. Using 7 as a private key? What a joke. The CAs aren't worthy of trust.
We already have to trust the domain name registrars anyway, since CAs query them to figure out if you own a domain before signing a certificate. In total, removing CAs would not only simplify the system. But it would allow scoped signatures. And we'd end up needing to trust far fewer actors to have a secure internet.
Why would I trust my domain registrar to maintain PKI? They don’t seem inherently better suited for it, and in various ways are more susceptible to meddling for e.g. ccTLDs.
I think the idea that CAs are uniquely incompetent is probably incorrect.
> One big problem with the CA system is that any CA - even the most incompetent - can sign certificates for any domain.
Is this not what CAA records were intended to solve? It seems like in practice they're only used by CAs to decide if they can sign a cert for a given domain, but it seems like a client could use it to determine if a server cert was from the correct CA.