Yes, xe did. Xe explicitly compares it to the findability of one of xyr articles that mentions Squid Game.
Why that made up pronoun?
I can see why commenter wouldn't call author 'him'. Why would anyone bother to track authors gender if it's irrelevant for the topic?
Pedantically, all words are made up. I'd assume GP is using it because they see utility in a unambiguously-singular gender-nonspecific pronoun, opposed to the more widespread but somewhat ambiguous singular "they".
Especially when there is an established gender neutral pronoun: they