Well, if they'd buy solar and some battery backup, and use mini splits for zone heating, winter wouldn't be too bad. Problem is, everyone thinks it's too expensive. My wife and I now spend nearly all our time in one part of the house, which is the part we condition. 400 sq ft is big enough for all we do, and though we have 2000 sq ft more, we hardly ever go over there. PG&E pays us each month for power we sell to them, rather than us paying them $300/ mo.
It seems to me that the "American Dream" is to own a 4000 sq ft house and then rattle around in it feeling they've arrived. Usually the kids have married and moved away, and they really don't need more that about 500 sq ft. "Need" is something inside people's heads. My wife likes having all that room next door "in case the kids come to visit" but that happens only about twice a year. Most of the kids are too busy to come by, now living in other states, and even the close ones tell us they're too busy, and can't we just come over there. Our closest daughter lives 40 miles away and brings the family by about once a year to collect Christmas presents. We visit them several times a month.