Lithium batteries are 3.6 volts per cell (nominal), 3 cells is only 11.25 volts, which is too low. 4 cells is 14.4. The existing electrical system was not designed for 48 volts, but was capable of running the 4 cell lithium ion low voltage with minimal modifications.
- 16v low voltage, really? Why not 13v, or go all the way to 48 like Cybertruck?
Virtually all 12 volt systems can and do run at voltages significantly higher than 12 volts. Most newer ICE cars run the voltage at 13.5 to 14.5.
All this made it a no brainer to move to a four cell lithium ion low voltage battery due to it's increased reliability over a lead acid battery.
I have no doubt all future Tesla's as well as the automotive industry as a whole will move to the 48 volt architecture.
As for the other stuff, many of them have a setting you can change on the touch screen. As for insurance, easy fix, go with someone else.