I think a big barrier to adoption here is that your Android phone most likely won't kill you if it has a bad bug[0].

Comma almost certainly won't get widespread adoption until it has enough miles driven on it (at least a billion?) for people to have enough data to start talking about its safety record. So that means it'll be stuck in the realm of enthusiasts for quite a long time.

If it does prove itself, though, I agree with you that it could be a game-changer for people who have recent enough cars to be supported, but not have their own driver-assist systems. And that's probably a lot of cars, and a lot of people.

[0] Although, with the exploding batteries debacle...