What "tells" have you noticed for AI-generated text (i.e., typical words/phrases, or other patterns indicative of GenAI)?

British style phrasing in sentence structure.

There have been a lot of comments already, but the stupid em dash is one of the biggest giveaways. The other is an overall generated "nice" article, instead of actually having "meat" to the article that talks about the concept in a certain way other than just being upbeat and positive.

Mechanical cadence and rhythm to the writing. No adjectives or wording related to emotions. It takes suggested tones to the extreme (example: formal is 200% formal). It's too perfect.

"In today's ever-evolving [BLANK] environment," three attributes in a row, "BLANK, not BLANK", the cursed em dash.

The inclusion of Markdown ASCII prepending or wrapping of words and phrases

i.e.
# for headings
* for bullet lists
** bold **
etc... etc...