Where it says, " "Few drivers would take the chance." said Davis. Most likely, they would get out of their car and simply walk away," I wonder if that's realistic. I'd think it more likely the car owners would call their dealers in outrage. Chances are, if one person has it, it's going to be widespread, and tons of people are going to be calling the dealers in outrage. I can see long backlogs waiting to get in and get use of their cars back. If the dealers themselves aren't crippled by the attacks.
I wonder if instead of demanding hundreds of dollars from car owners to get use of their cars, the ransomeware authors said, "pay us (something small) and we'll leave you alone" that they'd be more successful. With the choice of something small like 25 or $50 weighed against weeks or months waiting to get the car into the dealer, would most people pay that?
We are reaping the seeds we have sown. If the carmakers, or even better the lawmakers, mandated that physical access must be the only way to gain access to a car's systems, you'd almost certainly completely inhibit the chances of this happening. But no, we demand more features and convenience than this will provide. Fine, but don't come crying to me when you get hacked :-)