This isn't a "gotcha" experiment, it's a real question. And the problem with "I know it when I see it" is that right now people are biasing towards "if it's good it must be AI" and accusing legit artists and writers of being AI.

I happened to me. I spent 10 minutes writing a reddit comment. I researched it, I sourced it. It had sections with headlines, bullets, and even em dashes. 100% written by me.

As soon as I posted it, it was downvoted and I got PMs saying "don't post this AI slop!".

The problem is the AI has been trained on well executed material, and when you execute well, you look like an AI.