I understand what you mean, but many people's skin is adapted. That's why skin awareness is important, it's a genetical heritage that tells you where you come from.

If I were to permanently live in the African savanna or Norway, then my skin wouldn't be as prepared, and I would need to take extra measures regularly, either by covering my skin, taking supplements, etc.

However, my skin is prepared to handle the average radiation of my region. I have never used sun cream, and if I'm going to be overexposed for whatever reason (during the 5% yearly window where the sun's intensity is above average), a hat and long sleeves are enough.