[nabeelahmed13]

As another ardent user I actually think it is a good but unfortunate heuristic.

Previously I rarely saw it used in my English-as-second-language peer group, even by otherwise decent writers. Now I see it everywhere in personal/professional updates in my feed by. The simpler assumption is that people over-rely on LLMs for crafting these posts, and LLMs disproportionately use em dashes.