It’s not about safety. These things don’t actually work yet. They can’t make left turns across traffic, they can’t change lanes in heavy traffic, they can’t handle anything but pristine perfectly mapped roads in good weather during daylight. Any non-standard street feature or road usage is an insurmountable roadblock (literally) to them. Promising that they will save lives and disrupt the economy (how you turn robot taxis into a profitable business hasn’t been explained convincingly for that matter) is a hollow delusion until they can actually navigate from point to point in less than perfect conditions without causing traffic backups or making the passengers carsick.