BY LAW, all vehicles operating in autonomous modes without a safety driver present should be required to have an obvious EMERGENCY STOP button accessible from the outside, which is active when the car isn't in motion or is moving slowly. It is utterly unreasonable that there is no way to stop or prevent the motion of these vehicles in emergency situations without the time consuming and often impractical need to access apps or make phone calls -- by then it will often be too late. At least with a human driver you can go bang on their window and say, "Hey STOP, there's a hazard!" -- but fascist-loving Big Tech Billionaire CEOs don't give a damn how many people they hurt with their tech. Get this goddamned tech under control, and tax the billionaires out of existence!
Do elevators still have emergency stop buttons? I don't remember seeing one in the last 10+ years.
Re location of the button on cars: I would guess that fire alarm pull stations/button stations have had lots of thought put into making them easy to use and discouraging prank use. I would guess that lots of that would translate.
I'm also curious whether throwing a tarp over some part of the sensors would actually be effective today.