fun fact about phoenix, going outside on a day that's about 100f, is not fucking pleasant they literally have air misters to help provide cooling, which barely does anything.

People are just fucking insane and will live in places like alaska where the ground is literally frozen all year round. Phoneix AZ is not "habitable", it's bearable. Also a lot of these places, especially in hotter dryer regions, will have covered sidewalks to provide shade, (at least historically) people would and still do wear large hats to block a lot of the sun. Even then a lot of people wouldn't spend a whole bunch of time outside in that heat.

also, have you seen death valley? It kills people, every fucking year.

That's why I used the qualifier "really" and in another comment I mentioned "in average temperate climates" If you were more familiar with statistics you would understand how means and outliers work. Just like someone can score a movie an 11/10 or a -1/10, it is possible for the weather to exceed 100F or drop below 0F. Just not typical.

And while I didn't say it specifically, 0F is similarly the average lowest temperature a person can tolerate/expect before beginning to experience problems.