WTF is up with Waymo?

Was driving a friends car to do a short errand. Was behind a Waymo at a light. Light changed and the Waymo limped through the intersection then seemed to balk at a Caltrain train track. It started to back up and then pull forward. Did this several times and I could not get around it. Though I knew it would not help, I laid on the horn. The passenger door even opened and closed once though there was no one in the car.

I was completely trapped behind that f'ing Waymo. Finally the intersection cleared, the light changed and the other drivers let me back up and get around that f'ing Waymo. Is this happening to other people? It was terrifying.