My parents, born in the 1920s and raised in Brooklyn never even considered air conditioning for our south Shore LI home. I, on the other hand, never having suffered a Brooklyn summer, never considered living without AC once I was on my own.
It was a huge mistake and that first summer was he!!. We survived but by the second summer we had air conditioning. It might be the difference in architecture, a brand new home or maybe the area was warmer and more humid. But no doubt we needed air-conditioning!
As we have learned in our travels, the East, South, and Midwest can be miserable. It is the humidity that is a killer.
I often wonder what life was like in those areas 100 years ago. Worst of all, no deodorant and a once-a-year bath (whether you needed it or not).