Right, my Stockholm apartment was built in the 90's, so it's not exactly super-modern, but it still has triple-glaze windows, very well-insulated outer walls, and is connected to Stockholm's district heating system, which generates heat by burning trash. The whole building uses a trickle of heat, and my tiled bathroom is still nice and warm, and I can get scalding hot water from the taps if I want it.

There are literally zero drawbacks to the way it's constructed and heated, no compromise needed, so this HN Ask is so weird to me, and it's clear that me and OP live in completely different worlds.