very surprising that Waymo would describe the accident in terms that blame the other party
If it drives better than a human (in this case it sounds like it probably did), that's good enough for me.
You don't just get to careen into a collision because someone else is not following the rules of the road, hoping for a payday.
Obviously Waymo vehicles should be slowing down to try to avoid a collision / reduce the severity. But in this case it sounds like the "fix" would be fundamentally changing the cars behavior to be far too conservative.