It fundamentally changes things because it's so easy to do anonymously. If someone drops rocks off an overpass, it's pretty easy for police to track them down and arrest them. If someone attaches a bomb to the bottom of a car, sure it's harder to get caught than dropping rocks off an overpass, but you still need physical access to the car, and it's still relatively traceable. But if remotely hacking a car, it would be pretty easy to stay anonymous. Plus, in both those other cases it's obviously foul play, whereas if a hacked car runs into a wall it's probably not going to be so obvious.

Plus, the anonymous nature of the internet makes it much easier to become detached from the real-life consequences of your actions. Just look at all the examples of online harassment from people who would never say things like that in real life. Look at people who go and grief kids' minecraft servers, yet wouldn't go and kick over their sand castles in real life. Look at morons who swat people.

Actually, come to think of it, maybe it's not so different - if it was found that a big car manufacturer had a problem with their door locks and you could open it just by sticking a toothpick in, you can bet they would take the blame once they started getting stolen.

I'm not saying the responsibility is solely on the manufacturer, but they definitely bear a major part of it. When you buy a car, you expect a reasonable amount of security. I guess the question is where we draw the line as to what counts as reasonable.