Not sure if it changes your point at all, but the changes were to the manufacturing operating system, not the car OS. I'm not familiar with manufacturing but I imagine there are a ton of different systems and perhaps not all are as secure as the other. I recall reading they needed some paint improvements, so perhaps they changed something there. I don't imagine they would have software controlling paint totally locked down.
Most manufacturing machines run G-code. Simply changing one of the G-code values (text editing) would cause the machine to make parts incorrectly, and this would screw up things down the line. https://en.wikipedia.org/wiki/G-code
on my Haas mill, the code is directly editable by the operator. On my robots, the code is 'taught' by moving the arm and telling the machine that the new location is the updated. It is routine to have to adjust minor things in the robots, the operator would have to have access to do their job.
I had a welder put a washer under a sensor on my robot one time, making every weld 1 mm in the wrong spot. We couldn't figure it out and ended up reprogramming the entire setup, 8 hours, to fix it. A week later I noticed the washer, put there by a guy who I fired for bad attitude a week before. Once I had found the washer, I had the choice of going back to the old code, or leaving it with the new code.
I left it with the new code. I didn't have another 8 hours to waste to fix the fix.
Even tiny companies like mine can have sabotage. Why not Tesla?
