Do you not read books or something? These dashes have been in almost every novel I've ever read. They're a pretty common linguistic convention if you spend any time consuming media that isn't written in dumbed down internet lingo.

Dude. I learned to use a double dash for effect back in 1986 and I have used the hell out of that fucker ever since. Stop pretending that there's one magical symbol that determines 100% that something was written by AI.

Oh ok. So you're a moron. I understand.

This isn't as universally true as a lot of people seem to think. I'm not defending this particular article, as I haven't even read it yet. However MS Word has been auto updating a dash to an em dash for years. Where do you think AI got it from in the first place?

It can be a marker for text that is written in places where plain text is preserved. In a written article that most likely started as a word document? Not always the case.

AI learned that from training data, which means it was used by humans writing this kind of text. At least that was true before AI started feeding on itself.