And a thing blocking the road isn’t exactly unforeseen either.
Tesla’s system intentionally assumes “a thing blocking the road” is a sensor error.
They have said if they don’t do that, about every hour or so you’d drive past a building and it would slam on the brakes and stop in the middle of the road for no reason (and then, probably, a car would crash into you from behind).
The good sensors used by companies like Waymo don’t have that problem. They are very accurate.