These car-branded laptops are never particularly great, they just look cool

A kill switch is just a switch. Wire it in between power & some necessary device. A cleaner setup would involve a relay. An alarm shop can probably set it up for you.

Install a hidden kill switch. When you turn the car on you have to flip the hidden switch or the car won’t start.

I’ll bet that auto start/stop makes this worse. Just think about someone in a cold climate who only drives around town with the engine off & heat on at every light. No way the oil gets up to temperature.