You're implying that car-theft would be equally as bad or worse than phone-theft. I'm not sure that's true for everyone. Further, stealing a car may be more difficult than stealing a phone.
Cheers.
And those are publicly known capabilities. You should assume that potential adversaries will have more than that. Am I certain that such exploits are known for the very most recent iPhone/iOS? No. But it would still be foolish to bet on them not being known.
Stealing it may be more difficult, but it's much easier to lose a phone than a car. I've never lost my car, but I've lost 2 phones (I got one of them back).