My wife is a journalist and has always loved them.

Now she's been accused of using AI for her pieces.

Oh well.

AI raised awareness of em-dashes among people who didn't/don't read much, especially the kind of long-form writing that LLMs have been trained on. Treating em-dashes as a tell of LLM output is a form of unintentional "vice signalling".

I do use fewer em-dashes now, but only because I spend more time on Linux, where my habitual Windows trick of alt + 0151 no longer works.

I think it's both. People started writing AI comments and also started using em-dashes. However when my former boss would write emails with AI he would add intentional typos and remove all dashes.

For my part, editing Wikipedia raised my awareness of the different types of dashes, and when to use them appropriately. Unfortunately, my Chromebook is not so forthcoming in ease of input.

If anything I use them _less_ now thanks to this whole thing.

Unconsciously and consciously yes, and this new awareness means others are now consciously avoiding the use of them so their writing is less likely to be perceived as AI generated junk

I know I did. I don't want eloquent punctuation to fall exclusively to the clankers.

In my case, yes. I have never used AI to write any prose (including HN comments), and I never will. But I certainly started using them more often since the ChatGPT era began, purely through osmosis. I'm not exactly proud of that, but there you have it.

I don't think my phone keyboard even has one to type

Surely yes, but also surely neglibly compared to the rise of slop being posted. Sometimes things are what they seem!