This reminds me of those trick “proofs” where by simple algebra you wind up with a “proof” that “1=0” or some such… provided nobody notices you divided by zero in an intermediary step.
Notice that at this point in the essay the word “better”, as in “better person”, doesn’t actually mean anything. From here, he goes on to tie it to “moral superiority”, but this is begging the question, concluding just 2 paraggraphs lower that “You can just look at it and see 1=0”. Er, sorry, “..and see it’s creepy.” Typo.
By introducing a nonsense term, he got from the reasonable and common assumption that IQ is a meaningful indicator about some baseline quality (which it only is a very little bit, at best, but, eh, it is) to, in just a step or two, nonsense — that being that using IQ as a meaningful indicator is “creepy”.
It’s very subtle.
This entire piece reminds me of the claim that intelligent people are much more likely to believe strongly in nonsensical things, because they’re much more skilled at coming up with ingenious, subtly nuanced rationalizations for their preferred malarkey.