Signal does store important metadata: the phone number itself. In many countries, you cannot purchase a SIM card now without showing ID, and the seller takes do

Signal does store important metadata: the phone number itself. In many countries, you cannot purchase a SIM card now without showing ID, and the seller takes down your ID details and forwards them to the state. Then your phone number is inextricably linked to your identity. Yes, the contents of messages may be securely encrypted, but many states can easily determine which of their own citizens (and visitors to the country who bought a local SIM) are using Signal.