. . . and no hacker would ever disable your vehicle just for the fun of it!
The biggest concern isn’t hacking, in that it could easily have a 1024-bit code known only to your service that could only be misused if they lost security over it. As someone else pointed out, the biggest problem would be if government tried to mandate it. Which they probably would. Damn them.
Its biggest vulnerability to this would be that it would have to be part of the manufacturer’s electronics, like their damn black boxes, and they would also want to include GPS tracking at the same time, making every car a surveillance tool to spy on its owner.
It is truly sad that government thinks this way. A combination of laziness and paranoia, using the catch-all of tyrants everywhere: “safety”, to justify endless intrusion and voyeurism.