Curious, what is "take control at a moments notice" in seconds? From what I've read about aviation, situations where really fast, let's say <2 seconds, reaction to an unusual situation is necessary don't seem very common compared to car traffic? (Excluding starts and landings, even if a plane can do those on autopilot the pilots certainly are going to be fully attentive)
It seems like an airliner flying at altitude has quite large safety margins compared to a car on a highway.
I wouldn't call it larger safety margins. Many if not most of the cases where car drivers should take action are survivable if they don't; that's different for pilots in airplanes.
Pilots typically have more time to react, though (astronauts lie even further away along this axis; in cases where astronauts can take action to save their lives, they typically have even more time, but also, in many cases, there's no action that will save them)
As to the "take control at a moments notice": that's where the problem lies.
The arguments in "Ironies of Automation" (https://www.ise.ncsu.edu/nsf_itr/794B/papers/Bainbridge_1983...) such as "By taking away the easy parts of his task, automation can make the difficult parts of the human operator's task more difficult" haven't lost any of their power in the 30+ years since it was published.
Because of that, I doubt the typical driver will be able to handle emergency situations, as it will require frequent training.
Tell that to a pilot who's had an autopilot failure where a servo went crazy all of a sudden. You better act quick, especially in low visibility situations, to turn it off, or pull the circuit breaker.
It might happen a bit slower than in a car, but the consequences can be much more dramatic.
How are the consequences much more dramatic while flying? I can think of plenty of scenarios while driving where you go from perfect autopilot conditions with no visible risks to death of passengers or pedestrians in <5 seconds.
Errm, I'm pretty sure the car equivalent of that would result in the vehicle swerving towards the side of a bridge at 70+ MPH, with very little chance of reacting quickly enough to turn it off. A car on the highway really doesn't have that much in the way of safety margins.
Even if the plane started falling down like a rock, you still have more time to react than a driver of a car where a tyre burst at 80mph and now the car is heading towards the incoming lane/rock face on the other side. You literally might have less than few seconds to impact and I imagine that if you weren't holding the steering wheel at the time, you won't be able to do anything.
It seems like an airliner flying at altitude has quite large safety margins compared to a car on a highway.