The em-dash has been standard at jobs I had over the past 20 years. Not necessarily a fan of lack of separation on both sides of the punctuation but it's the normal style.
That we commonly used em-dashes as a mark to set off parenthetical information. Yes, you can also use parentheses and they're somewhat interchangeable.
> On the plus side, I guess we can thank AI for bringing back the humble em-dash.
It was always there, and used. It was just typically restricted to pretty formal, polished writing (I should know, I have coworkers who fuss over em and en spaces). I bet if you looked, you'd find regular use of em-dashes in Newsweek articles, going back decades.
The things LLMs did was inject it into unsophisticated writing. It's really only an LLM tell if it's overused or used in an unexpected context (e.g. an 8th-grader's essay, an email message).
I tend to insert space before and after on the very rare occasion I might use one . . . However I'm from the colonies and I've just learnt my preference is likely due to British influence.
I mostly just use a double hyphen in casual/lazy writing like emails (or HN comments :-)) but use an em-dash in anything more formal. En-dashes just seem pedantic and I don't really use them in general.
