I live in a pretty hot climate, but it’s only really unbearable at times due to shoddy building and bad urban planning. Even then, summer can be difficult.
I can’t imagine what it’s like on the equator, especially in dense urban centres. What’s Mumbai, Bangkok, or Singapore like at the height of the wet season?! How do millions of people function day to day?
Being fat in hot climates is miserable. Had to take a shower after going to get the mail in the summer. In the mid 40s(5-8C?) and I’d be going around in a long sleeve shirt. By the time I should start to get cold, my body’s warmed up or I’m in a conditioned place.