I am having trouble imagining this scenario in a way that makes Waymo look as bad as you imply. It sounds like the human-driven vehicle if it was "boxed in" on an on-ramp needed to slow and merge, rather than racing to pass on the right, running off the road, and causing a spectacular single-vehicle wreck. The way it's described in that paragraph seems to be ironclad proof of the need to promptly relieve humans of driving tasks.