In all fairness, this isn't particularly new. Even going back much farther, things like the prius that was making the rounds after it was hacked. It did require physical access to the car, but then was able to be controlled wirelessly, IIRC.

The main thing most cars have in their favor is the inability for them to be updated/connected to wirelessly. At the same time, the ability to patch bugs that do show up, remotely, is really nice.

I think the responsible thing for any company, especially one making widely used software, is to have a robust bug bounty program. Pay people to exploit and break your software, then fix it.