I know that the car reports practically all user events to Tesla in real time over the cell network (eg, open door), and I know it has root access. I don't know if that root is available remotely and I don't know if foundational commands like steering, acceleration and brake are accessible via the CLI (they are computer controlled actions locally)
THUS I would not want to drive a Tesla if there was the possibility of all cars being rooted and remotely controlled by an unauthorized actor.
https://www.wired.com/2015/07/hackers-remotely-kill-jeep-hig...
Think of it this way: every concern you have about a teenager having root on their electric car is the same as any sociopath hacker (AI enabled for modern nightmare fuel) who finds a root vulnerability and decides to not be a good person with it. If a teenager can mess with the collision avoidance, e.g. Israel can modify it to murder anyone who talks shit about Israel in the car. Or the CIA could turn it into a weapon. Or one day some dev could push a bad OTA update. Et cetera. Our safety regulations should mandate design features to prevent a malfunctioning computer from posing any greater safety risk than any other modified part in the car.