Well, you're kind of being a bit of a bell-end about it, but some of your suggestions are correct, in terms of that's what the buildings lack in their architecture.
You know greenhouses, like you grow tomatoes in etc? They gather all the sun's heat and trap it inside, so it's hot and humid - but even in cold weather, they stay warm enough so seeds can germinate and plants don't die? That's what our houses are like.
Office buildings are especially bad for it. Big fancy glass thing. Triple glazed. No openable windows. No shutters. No curtains.
Houses likewise, you can open all the windows in the house, but there's high humidity and no air movement, so it just sits. A fan can help a little in a localised space.
Even shutting the curtains during strong sun doesn't do much - external shutters would help - so the heat is stopped before it's trapped behind the glass - but it, or air conditioning things are a lot to go through for 3 weeks of too-hot weather, compared to 8 weeks of temperate weather and 41 weeks of too cold weather.