I could see that possibly being true. I mean, driving is kind of weird; it seems to be mostly done with a part of the brain that can operate automatically with little conscious effort. It's sort of like playing the piano: if I'm playing some piece that I know well I probably won't screw up unless I actually try to consciously think about what I'm doing, which is when things fall apart.

That said, I think people should be reasonably safety-conscious about vehicle maintenance, avoiding risky situations, and avoiding things that could sabotage the automatic-driving part of their brain, like doing other things at the same time that require their attention and their hands and eyes.

Agree!

Now I'm really curious for the reasoning behind that.

I think it's like the difference between balancing on a plank of wood a foot off the ground and one ten feet off the ground. The act is the same, but the perception of risk is way different and the performance would be as well

It's not even about confidence. It's a matter of being in control. When you drive you can do something about whether or not you crash. When you are a passenger in a plane or train you are completely helpless.

Apparently, such confidence is misplaced, and people "in control" crash a lot more often than helpless passengers.

Or everyone’s overconfidence and underestimation means there’s no appetite for people to accept regulation and change. because I’m not the problem and I’m in control, I shouldn’t expect change. Meanwhile when you fly, you know you’re at the hands of someone else, and you want to control them as much as possible.

You don't even have to use a plane as an example.

Be a passenger in a car with a driver you're unfamiliar with. Lots of people struggle with that and way overestimate the speeds the driver is going at.