Regarding older designs, from the 30s through the 60’s, it was considered good design to install and calculate out long eaves on the south side of the bldg and narrower eaves on the north side,...to favor more shade on the bldg walls in the summer and more sunlight in the winter.
That feature is no longer in the codes. Most newer homes leave off the eaves except for snow melting.
Not just deeper eaves on the southerly exposure but second floor porches such that sunlight never hit the exterior wall. Used to see many such wood frame houses in Newport News, in the fifties. Quite comfortable for most of the summer until you got closer to triple digit heat with high humidity.
Keep in mind also that there were virtually no heat producing electrical appliances such as we have now. Light bulbs were rarely larger than 60 watts and used more for task lighting; desk and table lamps and maybe a floor lamp or two. So there was very little heat gain from lighting.
As for electric appliances there were virtually none aside from a refrigerator which was tiny by today's standards and maybe having a freezer shelf or an ice tray or two. Aside from that add a tube radio and record player that was it until television came along.