Alternatively, someone leaks an SGX exploit that bypasses it all, and we wonder whether it was a mistake like so many other vulnerabilities, or if someone deliberately put it there because they didn't believe in Intel having that amount of control... "I wish for the insecurity that brings us freedom."
SGX doesn't really give Intel "control" in the sense of taking away existing freedoms. It's a new feature. You can always elect not to use it, or not to use software that uses it.
That's always the excuse given for every new invasive user-hostile feature. The problem is when the majority of new applications and websites require it. You can always elect not to use a computer either, but I think such a position would be untenable even for a "extreme Stallmanist".
https://software.intel.com/en-us/articles/intel-trusted-exec...
Details: if the key used to sign architectural enclaves (like the Launch Enclave) would leak, this would completely break SGX. Anyone with the key could create their own Quoting Enclave and the guarantees behind software attestation would go down the drain.
I want to use SGX to protect cryptographic keys. Attestation is mostly unnecessary.
For normal computing, as long as you control the machines and can bootstrap trust yourself, you don't need Intel's attestation mechanism at all. You do, however, need to ability to launch an enclave.
If the OS is evil and you don't do attestation, it can emulate SGX and run your code in a simulated enclave environment where EGETKEY returns keys that the OS knows about.
If the OS is not evil, you can use process isolation to generate and protect the keys.
Ignoring the cloud computing aspect of SGX, no amount of attestation can recover from your-OS-is-compromised-from-day-one scenario. The attestation is only as good as its verifier.