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.
Apparently it's #2 is the US with 37% of homes.
https://www.climatecentral.org/news/your-heating-fuel-depend...
Now that I live in a single family house I use oil to heat the house - but the boiler requires electricity.
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.