Extending the chain of trust down to the source of information isn't exactly going to happen at a snap of a finger. If you trust TLS and trust what the server g

Extending the chain of trust down to the source of information isn't exactly going to happen at a snap of a finger. If you trust TLS and trust what the server gives you then today that is a fine option, the server is signing a piece of information and giving it to you, this is no different from you signing a transaction and publishing that transaction to bitcoin the trust ends in just the same way in each case with the caveat of 'value' being created from a web service. An attacker gains access to either the producer of the transaction (client code or web service) or the keys to sign the transaction (tls or bitcoin private key). That said I agree that modern web services could much more easily be made to give an incorrect response. I don't think your argument applies any differently to other cryptography, it all looks like jumping through hoops for no guaranteed safety. If you believe that the only thing that matters is 100% safety then you are going to be very disappointed with computer security in general.