There’s an argument to be made that this allows better integration between subsystems, and therefore a better user experience.
We have a vehicle built this way. It is a death trap. Most of its safety issues can’t really be blamed on it using a new computer network technology. For instance, if it is dawn or dusk (so, commute hours) the vision systems get flaky and it likes to override steering and brakes to force itself into oncoming or merging traffic.
However, one issue is firmly due to it being a software defined vehicle.
If you are changing lanes with the turn signal on, and hit a bump while the passenger adjusts the stereo volume, they’ll accidentally turn the hazard lights on. Af that point the steering override will kick in and try to force abort the lane change.
A normal car wouldn’t be able to wire the hazards into the power steering subsystem, and also probably wouldn’t have the button be part of the radio control panel.
