It's the same as with climate talk in general. "Ooh, the average yearly temperature only rose this much, or even fell down relative to 5/10/20 years ago." - sure, but if the range of temperatures keeps growing, you can end up with both a nice average falling year over year, and uninhabitable land due to all useful vegetation freezing up or drying up.
I fully disagree with your use of "extreme" here, you have no evidence for that. Homes naturally have insulation which would mean the +22 temperatures would heat them, and some of that leftover heat would therefore reduce the need for heating. Indeed, it seems likely to me that the rate of heat leach would keep both these situations identical except for the fact you managed to inject "also using AC" in here like anyone ever does that.
Quite a weak argument.
The overall climate of our planet has nothing to do with the energy cost to heat a home.
Resistance heating is linear. Furnaces using slightly colder outside air are just a tiny bit less efficient, but it’s really close to linear. Heat pumps are non linear and do use electricity from natural gas.
