Hmm does 48V really need to be disconnected? What's the reasoning? Honest question: is there something else than path dependence preventing just switching ever

Hmm does 48V really need to be disconnected? What's the reasoning? Honest question: is there something else than path dependence preventing just switching everything in a car from 12V to 48V? Even interior lighting? Ie is there some place where 12V is actually significantly better for physics reasons?