A lot of this is a game of probabilities, which I don’t really think we have.
For instance if a normal human driver, without any automation, can prevent 80% of dangerous situations, but the automation can only prevent 50%, and in those situations the human savety driver can prevent only another 50%, because of inattention, this results in just 75% of dangerous situations prevented and the automation is worse.
Maybe someone knows the real probabilities, I don’t.
NixOS would be like brewing coffee with laboratory equipment and then setting it up for automation.