It is very tempting to think that, but the reality is that cars are becoming complex interconnected systems. The mode of operations has for many years been brute-force implementation of individual subsystems with minimal coupling between them. Implementing a hundred of these separate subsystems at, say, $10 each adds $1,000 to the BOM for a car. Replace that with a higher-capability shared subsystem that does all of it for, say $100, is a clear win.
It can also be a win technically. In individual subsystems any interaction between subsystems requires foreplanning and direct connectivity. With centralized resources interconnectivity becomes a software decision that can be made differently in later releases, without hardware changes. Think of it as a mobile SDN.
So may microprocessors, so many interconnects, so much multiplicity of operating systems - just to drive a car!
Why can't somebody put a kind of just a single mini-server to do all those jobs without creating this jungle of processors , their memories , their peripherals and the mesh of CAn , LIN, TCP/Ip and all that.
A robust single processor system should be able to minimize this whole mess to a reliable real time embedded system handling Engine control, Navigation, multimedia, ABS, Parking assistance and whatever you can name .