The SIM card is really the original secure enclave, and even has protected storage of contacts and messages, and early mobile payment solutions in Asia and Euro

The SIM card is really the original secure enclave, and even has protected storage of contacts and messages, and early mobile payment solutions in Asia and Europe used the SIM card to securely store payment secrets. Unfortunately, mobile operators have been pretty terrible at keeping up with security (neglecting to block old and broken voice crypto etc)