The key question is what competitors have as technology. I don't know about the Japanese manufacturers, but in Germany Audi and VW have been heavily working on self-driving and assistive technology for the last decade and only incorporated communication technology at a later point (I was working at Vodafone R&D then and our team participated in joint tests starting six years ago). It is safe to assume that Google's approach was comms and data-first, car-physics secondary, while the manufacturers approach is the other way round with a focus on mechanics and physics.