I read about Tesla's 48V system. They're advocating distributed controllers with local wiring to switches, sensors, and actuators, and power and network to the distributed controllers. BFD. Everyone is already moving in that direction - most cars have dozens of control modules on the network. The local high-speed network for the steer-by-wire is how Toyota/Lexus is doing it, too. Ethernet instead of Canbus is prompted by the need to transmit more data due to all the cameras and other sensors involved with driver-assistance systems. That transition has already been in the works for quite a while. A lot of vehicles already have multiple on-board networks.
One of the nuisances is that (low-speed-network) OBDII (which started production in 1996 before anyone ever thought of needing networked video on a vehicle!) is a "thou shalt" on any vehicle that has an internal combustion engine, which means you're stuck with that low-speed CANbus even if other stuff in the vehicle needs a high-speed network
None of this is "new", everyone already knows how to do this, the cybertruck is the first one to change over wholescale. Not building any vehicles that have internal combustion engines, and not needing to maintain network compatibility, makes that easier for them.
This is all well and good if you start from scratch and accept that nothing that is powered by electricity in your new vehicle is compatible with anything your existing suppliers and aftermarket parts manufacturers build. Power seat motors. Power window motors. Wiper motors. Windscreen washer fluid pump. Lighting. Audio equipment. The interface to the trailer that you want to tow, every single one of which has 12-volt lighting circuits.
I suspect they're going to have a few DC-to-DC step-down power supplies to power accessories that aren't compatible with 48 volts ...
There was talk some time ago of switching to 48 volts due to the power demand for electric power steering, but everyone figured out how to design low-voltage servo drives efficiently enough that the issue went away.