CAs solve a very specific threat model, governments or corporations are not included. It is purely designed to protect against Computer criminals with very limi

CAs solve a very specific threat model, governments or corporations are not included. It is purely designed to protect against Computer criminals with very limited resources. PKI is designed to be about as strong as the lock on your front door, experts and police could pick it or get a key from the manufacturer but many thieves will just break a window and run a small risk of being detected in the process. If we want real security we have to build it separate from the CA model, but as you point out CAs do provide some security against government inception, just as a locked door does provide some security against police wondering into your house, and we should not abandon it wholesale.