"I'm not OP, but to respond to question 1, allowing users to disable the feature would also allow attackers to disable the feature." Older products had jumpers

"I'm not OP, but to respond to question 1, allowing users to disable the feature would also allow attackers to disable the feature." Older products had jumpers, physical switches, or software mechanisms for securely updating firmware. The first two are immune to most types of remote attacks if done in hardware. Intel already uses signed updates for microcode which people aren't compromising remotely left and right. Intel supporting a mechanism like those that already existed in the market for disabling the backdoor would not give widespread, remote access to systems. If anything, it would block it by having less privileged, 0-day-ridden software running. I'll also note that the non-Intel market, from OpenPOWER to embedded, has options ranging from open firmware (incl Open Firmware itself) to physical mechanisms to 3rd-party-software. Intel is ignoring those on purpose for reasons they aren't disclosing to the users that also probably don't benefit them.