I've been using en and em dashes since the 1990s (with word processors and with LaTeX). I'm not the only one, either. As another commenter pointed out, no way am I going to alter the punctuation I use just because generative AI has hijacked and overused an aspect of that.
genAI is having a negative impact on too much stuff as it is. I, personally, refuse to alter my writing style just because genAI copies aspects of it. If some discount what I write as a result, that's a price I'm willing to pay.
The use of em (or en) dashes might indicate something has been written by AI, and there are reasons why this may be the case.
Or it is an indication that the message is typed on iOS.