Live in a high radiation zone and you can keep your whites white just by washing them in water and hanging them outside in the sun. No chemical bleach is necessary

All your other colors will head towards white as well. Reds, blues, etcetera will all bleach out. So they are actually less desirable and not good investments.

Even specially colorfast fabrics can't hold up very long against intense and broader spectrum UV radiation that showers much of the world near the equator.

So white is good. It can't bleach any lighter and it acts to reflect some of the rays of the sun. And in these regions, it's not the heat that does you in - its the radiation that you feel deep in your bones when your skin is not covered.