I found the reason, I found the article on LinkedIn, if you compare both links you'll see that mine is different because linkedIn added some stuff at the end of the url.
Of course, but that doesn't make checking before submitting difficult at all: bottom search box, enter a relevant keyword (e.g. "ignorance"), then sort by date. You'd see that it was posted twice before with the first getting 104 comments.
linkedIn added some stuff at the end of the url
Yes, many sites (e.g. medium, signalvnoise) add phony fragment identifiers to URLs now; I can't think of a reason to do so other than to evade dupe detection.
