In an economy where work is increasingly automated, those humans who can do things which machines can't are finding themselves more valued. That seems expected, and I am not convinced it is indicative of any problem or unfairness.
So what do we as a society do with those at a disadvantage, sometimes severe (eg IQ below 90?) we can move toward finding ways to include them, or we can move toward excluding them. The problem from the article is a societal one trend toward exclusion, not economic as you pointed out.
A just society judges and rewards people based on what they contribute. Racism, sexism, ageism, and the like are unfair not because they select based on something "outside your control", but because they deprive a person of the opportunity to succeed or fail based on merit.
Intelligence is a direct factor (though not the only factor) in a person's success at performing just about any job. If it is not a fair criteria by which to judge, then there are no fair criteria.
Edit: I read comments before the article as the HN discussion is typically more interesting than the article itself. Didn't realize this exact stat is in the article.