The sad part is that it would be easy to design a vehicle that's modern and connected and yet safe as far as the actual course of driving is concerned. Don't connect the drive systems to the same system as the rest of the car and you're pretty much gold (obvious exceptions of course).
Rule of thumb: if you can connect to it, it can be hacked.
edit: I've toyed with the idea of sitting down and designing the entire electrical system of a car from scratch, to kind of improve upon a lot of the complaints I have with most, but it'd be moot as I could never design the rest of the car, I'm not a mechanical engineer.
edit: same reason I'd never put a home security system (like door locks and stuff) on a system connected online, *** that. Hell I'd almost be paranoid enough to not connect cameras either. I mean the vast majority rely on security by obscurity, including myself. I don't think I'd ever want to be a public figure, if I were I'd have to go off the digital grid.