Earlier quoted context omitted.
Which is worse, proprietary closed system from car manufacturer or OSS system. There's as many pros on one side as cons on the other.
False dichotomy - I think it should be similar to Kerckhoffs's principle in the long run. OSS yes, but it's signed and audited when it's able to run. Maybe like an open source version of microcode updates for CPUs. You could file a pull request because you spotted a bug but you can't fuck around your car (bad, but not so bad) and other cars (very bad). If the Toyota code would be public we'd hear a lot of guys scream…
That is, the 'model' is the truth and the IP. The generated code is spaghetti, the vendors components are black boxes, and their 'code' is nothing more than another locked subsystem in the model.
Let's say in an ideal world, these mission critical systems must be opened - what do you propose everyone's business model should be? If everyone must see each others models... where is the free market competitive advantage to be gained?