You can compare all cars vs Tesla and you still have bad stats since Tesla are new and expensive cars, you can't compare with old cheap cars.

You can compare autopilot vs human drivers and is still bad stats because most of autopilot miles are on good conditions on big hihgways so you would need to compare on the exact same roads.

TL:DR you need stats for the similar driver population, similar car prices and age and drive assist, similar roads. The TFA asks for more transparency so we would get more data and maybe we get better stats or more bad statistics, that we need to debug.

1 they are not alpha/beta testing on public roads

2 not all cars track you, my brother Ford won't call to the homebase with crash info when he hit a dog.

Why would the model/price/class of the car affect the crash rate of a self driving car?