While I agree with your sentiment, I can already react to your post with the troll reaction even though there's nothing wrong with it. I can also put a dislike under a post that is actually useful to others just because I disagree with the poster's opinion while liking another post that adds nothing of value. Bad actors and stupid actors will always exist, regardless of the system.
To answer the question of how one would prove it, it's simple. You politely ask the poster to explain themselves, you have a discussion about it. The thing forums are for. "Hey, can I know where are you getting this from?" If they can cite their sources and explain their logic in a way that makes sense then it'd be less inclined to hit them with the bot reaction. If they can't do that, I'm hitting them with the bot emoji. Not to mention your entire posting history is available here. If some John Doe with no profile picture, a history of nothing but post reactions and nooby questions suddenly whips out an article of text that looks like it came of some encyclopedia of occult terms then that's a little sus (a little ironic since this is my first big reply, I know).
As for the issue of how one would identify the text of said post as AI there are already repetitive sentence structures and grammar that you can use to do that. It's just a matter of training the eye. The other easy solution is to ask one of the many AI chatbots out there to talk about the same topic that your suspected AI poster is talking about and compare outputs. Is it perfect? No, no detection method will ever be. But again, you're on a forum. If someone mislabels you as AI and you want defend yourself from that accusation they you should have no problem replying with receipts of where your information came from. Your posting history can also do the talking for you. Other users who know you for a long time will back you up.
Whether your hair is real or not has zero impact on me as forum user. But whether or not the information you are posting is real and based at least on what I perceive to be a true experience does have an impact on my experience as a forum user. I want a good well of information and a community of real practitioners to talk to and make sure my stuff is alright. That's why I came here, that's presumably why you went out your way to donate money to this place. AI posts dilute good information with useless and sometimes even hallucinated facts and people who rely on it to teach them stuff do not actually learn good practices from it and end up outsourcing their thinking to it. Having no reaction to someone calling you ugly is one thing, having no reaction to someone who's comparing you to a machine that doesn't even understand what it's output means should make you double take on what you just wrote and who's making that comparison. These things are not even remotely comparable.
