The machines are never going anywhere; the government invested zillions of dollars in them after the underpants bomber. Too many career civil servants would lose their jobs if they got sidelined.
But you're right: things will improve if most people refuse the strip search; the TSA will get better at pretending to screen the opt-outs, and the machines won't matter anymore.
One of the reasons for that is that civil service selects for people who are ultra conservative and sensitive about job security, and therefore are unlikely to allow a failed project to actually fail.
But you're right: things will improve if most people refuse the strip search; the TSA will get better at pretending to screen the opt-outs, and the machines won't matter anymore.