"When you sign up for a passcard, your registrar will give you a secret key" How is this decentralized if the registrar issues your secret keys for you? Couldn

"When you sign up for a passcard, your registrar will give you a secret key" How is this decentralized if the registrar issues your secret keys for you? Couldn't they hijack your identity at any time? It sounds more like a federated system of identity providers like OpenID.