This article is making a LOT of assumptions, not a lot of which are well founded. First of all, it's assuming largely that society as it is will still exist without huge changes and genetic engineering will not be major factors. Which is absurd, but a sane assumption to make for the sake of having an article that's coherent.

Beyond that, it's assumptions are too much based on a pop-culture view of 'caveman vs modern world' mentality. It assumes that 'anxiety and aggression' are selected against in a developed world, which isn't very well founded, and it assumes that anxiety and aggression are distinct, observable traits.

Furthermore, it's conflating 'societal beauty standards', 'personal sexual preference', 'person people want to breed with', and 'person people are likely to breed with' are all the same thing. Those are all separate groups. The first is a political thing more than anything divorced from the rest. And the second is a far cry from the third and forth.

And the assumption that gender differences will become more pronounced is not at all founded, really. We're in a trend of gender lines becoming more blurred. And it seems in direct opposition to it's vague concept that people will become 'more standardized' which seems to be the opposite of what's likely to happen.