Seriously? You're illustrating the point here. On low tech cars, an attacker has to hack the cars one-at-a-time. They could endanger one car load of people with each "job".

With high-tech cars, an attacker could hack every car of the same model. With thousands of Teslas on the road, I think it merits a higher concern than somebody with side cutters.

I thought it was obvious. Next time I'll let it go unsaid..

It's a wired-ethernet network not Wifi.

The attacker would still need physical access like the low-tech attacker to network and update software on the Tesla.

Also, the brake line could be cut in seconds whereas 'jailbreaking' and then flashing the drive control software would take ages in comparison.

yeah but the state police can examine a crash after the fact to determine a brake line was cut.

even if the software survives a high-speed crash, it's possible for the surreptitiously placed modification to erase itself as its final act. additionally, the surreptitiously placed modification can wait for weeks or months, giving the attacker time to build a cover story or misdirect or accomplish any number of other goals.

Now imagine someone hiding in the hood of your car waiting to cut your brakes while you are traveling 80mph down the freeway.

Is it even that complicated? Just cut one (or all 4) of the lines under the car that runs to the brake calipers. No need to get under the hood.

You're almost certainly going to notice you have no breaks way before you're going to be at a speed to do serious harm, especially in an urban setting.