Perhaps you're simply not as sensitized to it as me, since it is becoming rather a raw spot with me. Go back and read the article again, carefully. Note how all the explanations of difference are assumed to be essentially moral failings of westerners, to eat "properly" [1] or exercise. Note the ingrained assumption that if there's a difference between the isolated primitive and the Westerner, the Westerner is automatically in the wrong, be it in behaviors or gut biomes, which they actually have to remind themselves may not be true, though they don't actually come up with any other possible explanations.
Mind you, I don't disagree that there are dietary issues in the Western diet or that there are exercise issues, but it's still bad science to presume in advance those are the only explanations to be considered, be it explicitly assumed or implicitly assumed. There's a world of variables out there and we've barely begun to shine a light.
[1]: Can't resist scare quoting since a lot of the people telling us what is "proper" in the past 40-50 years have also been dead wrong and quite possibly the dominant reason we're eating wrong in the first place; if not the dominant reason then certainly a huge one.