Do you find your fridge or freezer highly complicated? Essentially the same technology as a heat pump. Much simpler than a typical modern gas boiler.Wood burning is carbon neutral if from sustained sources or wood waste. Every woodworker should have one, if they aren't living in a densely populated area.
There'll be plenty of wood waste around when we enter the impending scrap-iron age!
I do think heat pumps etc are extremely high/complicated tech, and will fail early in a crisis, if not sooner.
Low-tech insulation should be top of the agenda and not vulnerable.