But here you say that: Security can depend on social contract and not technology. But the same argument can be applied to your original objection. We can mandate (in the social contract) that people have the right to privacy. (And there are some analogs where we do that, for example, we could have Gattaca-like dystopia where people's access to health care is based on genetics, yet all developed countries have a ban on such discrimination.)
I think it's far more dangerous that the government or adversary is technologically capable of being non-transparent than if ordinary people don't have capability to be non-transparent. It's because I believe power ultimately thrives on information asymetry, and the encryption only amplifies this asymetry.