In one case, I could tell because the tone of the piece sounded exactly like the kind of stuff I would read after prompting an LLM and I had never heard of the author before, but I knew that they were like an intern or a new college grad and for some reason their piece was trying to persuade employees in a certain field about how they had to use AI itself. It just rubbed me the wrong way because if they did use AI, then they didn't even bother to rewrite the repetitive instances of "it's not X; it's y", and also "This isn't X".