I had 2 almost identical scenarios this week where cars stopped unexpectedly and it was only my experience made me pause to think why did they do that. Out of nowhere a police car raced through the gap I would have driven into if I didn't 'sense' something was wrong. From a visual and 'sensory' level there was no risk. I avoided 2 head-on collisions with a fast moving police car. A robotaxi would have proceded and crashed. Equally an overconfident young driver woud have done the same.