Didn't do forensics on author/submitter. But the parts I didn't quote mentioned up/down arrows and other things that sure sounded like HN to me. Finally, AFAIK, HN is the only one that fits that description (though I'll admit to a wide swath of ignorance related to social media in general).
OTOH, it is also a general comment whether the author is referring to HN or not. It always struck me as something that you'd find on, say, 4chan.
