If you’re driving, your brain can automatically prioritize the importance of things that you see. But since a computer fails in different ways than a human, you lose all automatic prioritization
One such study is "Performance consequences of automation-induced 'complacency'" (Parasuraman, Molloy & Singh, 1993) https://www.pacdeff.com/pdfs/Automation%20Induced%20Complace...
Previous studies had found that a human and a computer performed markedly better than either a human alone or a computer alone - but in those studies failures were quite common, so they didn't give the humans time to get bored or distracted.
When researchers got test subjects to perform a simulated flying task, monitoring a system with 99%+ reliability, they found the humans were proportionally much worse at stepping in than they were on less reliable systems.
Swimming pool lifeguards will often change posts every 15-20 minutes and and get a 10-15 minute break every hour, to keep things interesting enough that they can pay attention. Good luck getting drivers to do that.
Funny, I was going to mention exactly that. I'm a private pilot with a modern autopilot and flying is exhausting. Partly because the piston engine is rattling your brain the entire time but also because you're on high alert the entire time. You're always making sure the autopilot is keeping the plane on the blue (or green) line and is being predictable. And my smartwatch shows my heart rate is usually more elevated on autopilot than not.
A "self-driving" tesla is an adversary you need to supervise to make sure it doesn't take actions you wouldn't expect of a normal car.
As other posters have pointed out, it's like running an LLM with `--dangerously-skip-permissions`: I wouldn't `rm -rf /` my computer (or in the case of tesla, my life), but an AI might.