So essentially, phones should just turn themselves off when moving? I find it highly unlikely that such a law would get any traction (implementation seems rather difficult - by the time it's fully deployed, we'd have been better off putting efforts into self-driving cars). Companies have no chance of implementing this optionally: Why would I buy a car/phone I can't use as a passenger? Deaf passengers would be doubly upset, as the presumably-allowed voice-control features wouldn't be accessible to them.