To someone that knows nothing about car SW architecture, that is surprising to me, I would have expected a number of control loops for things like fuel injection, ABS brake control, drive-by-wire, EV battery charge and discharge, etc. each running on their own processor due real-time safety considerations. These I would expect to be different implementations and parameterizations of the same control theory maths.

On top of this comes some functionality to control windshield wipers, lighting, AC, seat heating, etc. Stuff which is probably not top-tier safety critical, but still important. I would expect that stuff to run on one, maybe two processors.

Then comes the infotainment system, running on its own processor.

Sensors are supplying data to all processors through some kind of modernized CAN bus and some sort of publisher/subscriber protocol. Maybe some safety critical sensors have dedicated wiring to the relevant processor.

A lot of variations on this seems possible with the same SW platform, tuned and parameterized properly. The real-time safety critical stuff would need care, but is doable.

Am I completely off the mark? Can you give some examples of where I am going wrong?