People’s bodies vary in their ability to cool itself. Some individuals are heat tolerant (cool themselves well) and some are heat intolerant (don’t perspire enough, face gets red easily in heat, nauseated, can get heatstroke). So I don’t get the premise that the OP’s author should establish what the rest of humanity should do.
Make it cold and I'm the other extreme. As long as my hands, feet and head are covered, I can shovel snow in shirtsleeves. A light jacket is okay, but if I wear what most people wear in the same type of weather, I start pouring sweat.
That’s true, but your bodies also tend to adjust to the conditions you are exposed to all the time. When I was younger and we only had a window unit in the parent’s bedroom, I could tolerate the heat a lot easier. Now, after being accustomed to air conditioning all the time, I can’t tolerate the heat much at all.