Comment by latexr

Blog posts, news articles, and other web texts have been using correct punctuation marks for a long time. I know because I’ve been noticing misuses (usually having switched or repeated characters for quotes) for over a decade.

Plenty of people care about typographic punctuation, and others use software (such as Apple’s OSs, markdown converters, publishing and editing tools) which auto-converts smart punctuation. Heck, tools for doing that are older than Markdown, and that is already two decades old.

https://daringfireball.net/projects/smartypants/

Look, nowhere have I said using an em-dash can’t be an indicator, my objection is people using it as the indicator. It’s become a meme. Too many people act like if the existence of a single em-dash immediately and conclusively proves it was written by an LLM. It does not.