Here's a random post from their blog by the same author from 2017 with an em dash:

> As we wrote before, we believe Blackbird Tech's dangerous new model of patent trolling — where they buy patents and then act their own attorneys in cases — may be a violation of the rules of professional ethics.

https://blog.cloudflare.com/patent-troll-battle-update-doubl...

ChatGPT didn't invent the em dash, some people were always using it. But yeah, it's often one of the signs of AI.

Too many think AI instead of horses.