Good point and I don't completely disagree with you, but title of article is "Which country has the best brains?" but not "Which country had the best brains?" or "Where were the best brains born"
I agree with you. It is still interesting to see the distribution of the noble winners. It is a good indicator of the countries that fund research and are pioneers in innovation.
I find it interesting that the worlds 2nd and 3rd largest economies, one of which has the worlds largest population, aren't even on the list.
As an example take this year's winners in physics. One of them is British citizen and one has a citizenship of Netherlands. An interesting fact is that both of them were born (an made their first steps in science) in Russia. Are these brains Russian or British/Dutch?