It’s perhaps an issue of the complexity of the operating environment and a lack of capability to formulate a working model through an electronics processing system.
Humans are not merely using just-in-time high level cognitive abilities to process a driving task. The senses-subconscious brain processes-spinal reflexes-instinctive behavior patterns-and intuition all play a part; such, that humans can often perform a familiar but skilled task, without continuous high level mental concentration.
That is so very true, especially with something like driving. I drive best when I'm well rested, but relaxed, and in away operating the vehicle without thinking about operating the vehicle. Sort of zen-driving. If one actually starts focussing on the pedals, shift lever, etc driving ability goes down. If you're in the zone, it's like you're part of the machine or the machine becomes part of you.
A proper mix of sensors and maybe even a splash of analog processing could go a long way toward reflex-like responses.