AI models are trained off the work of these writers, so they use them now. Except that the difference is that a writer will just use the - next to the `0` key, expecting that Word, Google Docs, or whatever is turning their markdown into rendered text will automatically turn it from - to an em dash, which is a different character.
The models are then provided that rendered or autocorrected text, and return text with the em dash, instead of the one we type.
iOS/iPadOS: long-press -
Windows: Alt + 0151 on the NumPad
I do like perplexity's style though, the organization of search results in comparison tables is nice