Debris tends to be stationary most of the time. Sounds like the car could have handled that.

I agree with that ADS being shit. Objects, once identified, should be accounted for in later updates in some form. E.g. in the way of "pedestrian now behind truck next to me". How the hell can an object switch status back and forth, loosing all its history? This should make the system be extra cautious at the very least. But yeah, safety doesn't seem to have been that big of a priority.