I'm not an evolutionary biologist, but it seems to me that the claimed magnitude of the change is wildly implausibly fast from an evolutionary perspective. I'm confused that neither the article, nor the paper it cites, addresses this.

To go from 10% to 30% in ~5 generations, the median-artery-having population would have had to expand by (30/10)^(1/5) = 25% more than the non-median artery population over each generation. It just seems totally implausible that median artery carriers could have that much more offspring.

This makes me pretty suspicious that the paper may be wrong.