That's what many OEMs have been doing for decades and this is exactly what many SDV have been trying to get rid of, since integrating many different products from many different manufacturers are slow, let alone iterating and designing new features.
Related to CAN, the bus is standard, but the thing is, CAN is just a bus, not a protocol. There are many ways you can have two ECUs (vehicle's modules) talking in incompatible ways.
Related to CAN, the bus is standard, but the thing is, CAN is just a bus, not a protocol. There are many ways you can have two ECUs (vehicle's modules) talking in incompatible ways.