Another way to look at this is how much effort should be demanded to maintain situational awareness. Asking for no effort is almost as bad as demanding full effort. In other words, too much automation makes people reliant on the automation. So when the automation fails, they’re lost. They don’t know what to do.
This is how people get in to trouble. They rely too heavily on automation and remain blissfully unaware of what is going on around them.
So imagine driving a car with stability systems and all wheel drive. It feels solid on the road — until it doesn’t. And then unless you’re really on the ball, your car will start skidding all over the place and you won’t be able to do much to keep from crashing in to something.
On the other hand, I used to drive a car with a five speed stick shift and front wheel drive. I didn’t even have ABS braking. I had total awareness of what that vehicle was doing on the road. I could feel the road getting slipperier and so I would back off on my speed, change gears, brake with caution and generally stay away from problems.
So which is better? Well, some drivers are inexperienced, distracted, fatigued, or generally oblivious. They would actually benefit from the more automated vehicle as long as they were aware enough to stay away from the truly ugly weather conditions. But many drivers would benefit from feeling the road without all that automated stuff hiding the details.
There is no right answer. In the airline business we have Boeing and we have Airbus. Both are highly automated, but the Boeing will do what the pilot tells the airliner to do, whereas the Airbus automates things more to keep the pilot out of trouble. There have been accidents both ways, some caused by pilot commanded errors, and some where the automation actually got in the way of the pilot’s commands.
Sometimes people really are so oblivious that automation would actually save more lives. And sometimes, the automation actually makes things worse by hiding the situation from the driver.