Why would they die in cold climate? I would expect them to die in hot climate (no AC - heat stroke, no refrigerator - food poisoning), not the cold where they would have wood/gas heating.
In lots of places that get very cold, even if the heat source is combustion, electricity is still used for ignition, control and distribution through the house.
Electricity is very predictable and not under control of one or two nations.
It's the same, on steroids.
which is more likely when they start vibe-coding grid managers