Brits, Dutch, Belgium, Northern Germany. They all have this incredibly outdated building style that they refuse to change. Bricks with no insulation. I live 1000km to the south of them and it is pretty standard for us to have tripple pane windows and thick insulation on our houses. But they for some reason prefer to live in cold houses during the winter and overheated houses during the summer.
I have had multiple conversations with people who lived a while in that area. Rich, educated countries, modern economies, but they live like they are poor farmers in the 19th century.
This has not been true for at least a decade for dutch buildings: there are strict regulations requiring decent insulation for new buildings. Renovating and insulating old buildings is also encouraged, but not required by law.
British building regs literally require insulation? It is not a law that old builds have to be brought up to code, but there were government schemes where you got free loft and cavity wall insulation in old houses.
I think the buildings really are that old - you can't legally build new ones like that in the EU afaik. No idea about Britain, but yeah, I lived there in a flat like that, it was over 100 years old.
Purely anecdotal, but every house I have ever visited in the Netherlands and Scandinavia has been properly heated and above all insulated. Which is absolutely not the case for the UK and even less so for France and countries further "south". If you want to be cold indoors in Europe, spend a winter in Spain, Portugal, Italy or Greece. Here I speak with some experience.