We operate cars on the road with not only no centralized system, but also minimally defined and enforced protocol, and yet Waymo has achieved a near zero collision rate inside a swarm of cars that are not running equivalent software. And this is in a situation where cars are only a few feet from each other while operating at top speed. So you can come up with a million objections but they are all solvable. As for automation failure, the rate of that can be easily made lower than the rate of human failure, which currently is fatal to a plane.