"Sun protection is good. UPF 30 or 50.
More effective than sunscreen."
I agree to a point. But really, unless you're albino, or you're on a equatorial mountain all day, very few really need a UPF 50 shirt.
I have a combo celtic-germanic type complexion. I have some red in my hair and especially in my beard, lots of freckles, rather light gray blue eyes, but can tan a little. I don't think i've ever experienced a sun burn through any kind of shirt, even thin cotton. I don't like sunscreen much and have been using clothes as my primary sunscreen for years now--i'm that dude on the beach and in the water wearing the white long sleeved shirt and tilley or desert style hat with sunglasses on.
There are conditions i've been in wherein a thin cotton shirt would not be good for UV protection, and i don't advocate black and whites in this area... (there are probably some conditions i've been in wherein i would have been burned if i had just worn a thin, somewhat loosely woven cotton shirt or the like).
Also (in my mind), there is some question of how much of the rise in skin cancer is purely from UV exposure, and how much it is being facilitated by a combo of over use of chemical based sun screens with really crappy, unnatural, and unhealthy diets and lifestyles which has become more and more common the world round.
When i do use sunscreen, i use a home made kind i make, that only has micronized zinc oxide powder in same.
We need a certain amount of sun and UV, in fact, far too many people get too little good vitamin D.
Life Extension magazine talks a lot about the need for a much more vitamin D in the body. One way for that is smart and controlled Sun exposure.
I'm not saying that you can't over do UV, course you can--that is obvious. In todays really interconnected world, you have all kinds of people living in climates that their bodies are not innately adapted to pigment wise. There are a lot of light skinned people living much closer to the equator than their ancestors tended to, and getting far more UV than they can naturally tolerate. So i think wearing clothes in the sun is important, but i do find the issue over hyped, even for my fairly light and burn easy complexion.