Ultimately DirecTV was able to kill pay TV hacking by simply introducing a new generation of cards that were better protected, the P4 series iirc. Other pay TV firms invested less and were mostly undermined by just one guy (Tarnovsky) - not exactly an army of reverse engineers.
The weak points in SGX security aren't the electronics themselves. So far all attacks on it are side channel based.
Still, the analogy applies because the stakes with a cryptocurrency that depends on transistor security become a much more interesting target then the, now boring++, paytv market. It should not be assumed that any secrets will stay inside of that secure enclave, at all.
++it's boring to hack paytv because streaming, downloads and card sharing removed a large bulk share of the need