There are myriad things that impact both actual temperature and perceived temperature. I don't even try to talk about any of the more "woo" sounding things that impact perceived temperature.
I'm just talking about well established design principles that were a time-honored tradition globally until recent decades popularized throwing money at the problem, using insulation and adding AC to shittily designed buildings. And I get nothing but grief most of the time.
Tempted to start blog number umpteen to bitch about this in specific. I'm calling it "While The World Burns." Maybe if people here keep pissing me off, it will actually get content and traction and yadda.
Historically, people were only interested in rubber necking at what a goddamned social train wreck waiting to happen I was. Maybe I can harness that bullshit for a change instead of trying to avoid it. Swim with the current, not against it.
But personally, I did not see yet an old building in Europe which is both warm in winter and cold in summer jusy by itself. The new insulation materials are really good now, there is no comparison with old techniques. My parents house is 200 years old, made of a wooden frame and brick. It is incredibly cold in winter, so cold that we need to burn wood as central heating is not powerful enough.
https://cleantechnica.com/2018/03/31/passive-solar-house-des...
https://en.m.wikipedia.org/wiki/Passive_house
Given increased heat from global warming, we can also borrow techniques from places like Mexico and the Middle East for cooling a house using air flow. For example:
https://en.m.wikipedia.org/wiki/Solar_chimney
https://energyeducation.ca/encyclopedia/Solar_chimney
We've been doing this around the world since well before we invented AC. We just seem to have conveniently "forgotten," never mind that these techniques are actually still in widespread use.
I get your confusion. I was actually reacting to this part of your comment specifically. I am for what you are saying. I just wanted to mention that modern buildings aren't always designed like that. In fact, where I live, houses seem to be increasingly designed to only keep the heat in, not let it out — as rightly pointed out above. That's a problem. We basically can't stay comfortable in summer sometimes. It's not pleasant sleeping on the upper floor during a heatwave and there's little we can do other than buy an AC (which we won't).
As a sidenote: our company just finished a new building which is designed in a similar way, but has active cooling via the heat pump/floor heating system. I hope that will work better than what we have in our private home.