Very few places use electricity for heat. It’s super inefficient unless you use a heat pump, and residential heat pumps typically don’t work too far below freezing.
Very few? Maybe for single family homes, but electric heat is very common in apartments - Every apartment I've ever lived in had electric baseboard heaters.
37% makes sense. When you live in a moderate climate and minimally need heating, low capex and high opex makes sense.
Too bad so many air conditioners don’t have reversing valves. One day I want to install a window-shaker “the wrong way” and see how well it works as a heater.
As an alternative, one could put water containers in their freezer and throw the ice outside as it freezes as a rudimentary sneakernet liquid<-> solid phase change heat pump.