@etchedpixels @futurebird From the "vintage" secondhand stores I've been to, can confirm. They were usually tatty AF, but perfectly serviceable.

For the aircon part, it's definitely true at least somewhat (Boston had an incident where the central library's HVAC was down for construction, and the newer half of the building was absolutely uninhabitable while the century-old half that predated aircon was just a little warmer than usual) but with the current heat in Europe, aircon is an absolute necessity. 100F and 60% humidity is generally not something you can "passive cooling" your way around.

That's not to say that modern building design couldn't be way better than it currently is though. The best way to help an AC keep the place cold is the older techniques to stop the heat getting inside in the first place. Stuff like awnings and louvers to keep the direct sunlight out of the building during the hottest parts of the year, that fell out of "fashion" as soon as AC became practical for some reason.