I don’t see much point in publishing such an article other than to promote some kind of racist tin foil hat guilt trip.
However, their facts are rather suspect since farming and domestication of plants began 8500 b.c. and it is known that there were already lighter skinned people in the Fertile Crescent and in the Sahel (Saharan) region at that time already and there were much darker skinned peoples in sub-Saharan Africa. And there were lighter skinned people in Southwest Asia and that was 10,500 years ago.
I don’t mean to poo poo these guys physiology or physics findings, but my sociological studies just don’t seem to somehow mesh with theirs. I suspect the ‘journalist’ who wrote this article took a huge dose of ‘journalist liberty’ (aka spin) with their findings for whatever purpose.
If you are interested in ‘sich’, a good quick read that was part of our studies is Guns, Germs and Steel by Jared Diamond.
I don't see any guilt in the article.