Aren't brakes and steering mostly manual? I don't think it's the right advice to tell people to trust Autopilot when it's failed in several egregious ways.
That said there are probably 5-20 systems in a car that can completely control these systems without any human input. Think of automatic emergency braking, traction control, vehicle stability control for the brakes, and autopark + powered steering for the steering.
Most of these systems have multiple redundancy and isolated monitors (eg, if autopark is on and the vehicle speed is > 10mph, the monitor will intervene) but there are still probably some theoretical situations where this could occur
Inifinity tried steer-by-wire but ended up retrofitting traditional hydraulic steering back.[1]