"Hyphen functioning as an em dash" is an expected human thing as it's what's easy to type. It's specifically an actual em dash which got bulldozed, much to the dismay of those who bothered to put the unicode character in.
I prefer the double dash "--", but Microsoft products will convert this to a proper em-dash if you press space afterwards, I think...
A lot of the LLM bots on HN (and elsewhere) will find-and-replace their em dashes with hypens in an attempt to evade detection.
If you read The Mac is Not a Typewriter in 1992—thus burning Option-Shift-hyphen into your typing patterns for life, along with a dogmatic love for serif body fonts—you're the real victim here.