LOL regarding the model 3 as a 'better' 12 volt management system.
In short, there is no 12 Volt management system. It is always running, and it uses a lot of power especially in temps lower than 50 degrees ambient. The car would never survive a month parked in cooler temps by itself. It loses 5% per day, just sitting. One of the more annoying aspects of Tesla ownership. Bolt, Spark EV, Kia Soul EV, even Leaf. I can leave sit for a couple weeks and the traction battery doesn't lose anything, and the car is generally ready to go. One more thing. Lose 12 Volts in anything but a Tesla, and you can use your jump pack and go. Lose 12 Volts in your Tesla, and it gets super annoying really quick.