The "expert" in the article got it wrong. The relationship between the voltage and the losses in the wires is not proportional. They are squared. Going from 12V to 48V is not a saving of 4x rather 16x.
For some applications you could also consider Power over Ethernet in the car, get both shielded comms and power. Or can and power over twisted pair.
For some applications you could also consider Power over Ethernet in the car, get both shielded comms and power. Or can and power over twisted pair.