[remram]

The certificates remain sound? What does that mean? Those certificates are never to be reused (ephemeral). Do you mean the signature remains valid and secure?

And whether the CA signs "identity information + public key" or "identity information + software hash", I don't see the different in "identities", no matter what that means to you.

Please, give a concrete example of information that is available/verifiable in one scheme and not the other. You both keep saying vague things like "it lacks identities" or "there's a binding" etc and I really don't see it.