By the time you are in the drivers seat, it will already be too late. A vehicle can't just stop and do nothing. A bad decision may be better than no decision at all.
It can in the scenarios listed above. If it sees the traffic lights blinking because a human is doing traffic control there, the car could safely stop and require a human to take over. If you're waiting behind someone who has stopped in the middle of the road to load or unload passengers, it's safe to just wait, or allow a human driver to figure out going around them.