Oh, I had them filed in by brain under “more efficient temperature control” but it looks like they don’t have an advantage over ACs when cooling. (Just over typical heaters, when heating). Oops.

That’s true however moving heat in the winter is much better than burning things.

Gas furnaces are 80%-98% efficient, heat pumps are 300-400%.

I think GP's point is that winter heating can shift to nuclear- and wind-powered instead of mostly burning fossil fuels.