[AlotOfReading]

Dealerships routinely violate CANbus isolation with junky "add-ons" full of security holes and wireless interfaces directly attached to important buses. Every single manufacturer that cares at all about bus integrity should be doing message signing and that's where CANBus simply doesn't work. The bandwidth is far too low for good schemes (leading to custom implementations) and there are no decent standards for hardware vendors to implement, which means more of the already-limited CPU budget has to be allocated to it.