I think you’re not really understanding the kind of housing this is made for. Shacks in slums don’t generally have nice triple glassed windows.

Yes, the alternative would be going outdoors. But in the tropics you don't want to do that during the midday sun.

No, people absolutely take the hot sun all the time when they have to go out, they need it because their homes are dark even in the day and there's stuff you want to do inside the house in the day, like cooking, cleaning, studying...

Yes, you have to be outside, but you wouldn't want to be, if you can avoid it.

In poorer areas, houses are sometimes made by essentially stacking up and leaning sheets of metal against a few pieces of wood, more or less. Decent windows often aren't a very viable solution. Light bulbs would be usable, but you sometimes have to get electricity (if available at all) by literally running a wire either directly to the power line or across the road and then stringing it up to the power line yourself. So your comment misses a key point about life in these countries.