Growing up in the US then living for quite some time in Europe it was initially weird for me to not see AC everywhere, but I quickly realized it was much more comfortable for me. Something about being in a cold building and then going out into a swamp heater just makes it more miserable. Maybe its slow acclimation or some subjective thing.

Not really acclimation, but willingness to suffer through it. I hate it when my children want to play outside because I'm out there for less than five minutes and my shirt is soaked through with sweat, it's unbearably hot, and the insects are legion. When I leave work in the late afternoon, it's so hot my car takes 10 minutes to cool down to where it's comfortable inside. By then my Right Guard has gone left and I'm having cold air blowing on wet skin. It really does suck.

And I mentioned same in my statement above. The entire lower half of the US would be largely unlivable without aircon. Even Alaska get 90+ in the summer, albeit for short bursts.