It is important to note here that that many automakers allegedly demand extremely high quality code from themselves. The MISRA C standard [1] is widely used as a guide for high quality embedded code in many industries and was developed by the Motor Industry Software Reliability Association.
Improving quality is not the solution. The issue is lack of a proper failsafe system - in this case, a STOP button that physically removes power from the ignition system.
No amount of quality can guarantee the computer cannot fail.
It's typically been my experience that (within limits) higher quality equals faster production. Can you imagine the debugging time they must burn with 11,000 global variables?
But your point is taken, it might well be feasible to demand aerospace quality code from the automakers.