Unless theymos gonna make or use AI which can detect whether a message is written by AI/not, there's nothing much we could do aside from reporting posts that doesn't make sense.
Using bots isn't even against the rules.
I'm impressed that the linked article was entirely AI.
Me too, and it makes me very curious where it gets its input data. Basically, it just made up some lies! What's the point in that?
I do see potential though, we'll have thousands of different AIs compete to join signature campaigns managed by other AIs. Or, thinking bigger, an AI can write those boring work reports. Then another AI can read it, and in the end nobody has to do anything anymore. Especially with the recent work from home, your own cloud AI can apply for thousands of jobs per minute pretending to be you, and since you don't have to show up in person anyway, your AI can maintain dozens of jobs

There's simpler & good horrible solution for this problem, which forcing user to solve CAPTCHA every time he made/edit message.
AIs are much better at it than humans. Try to solve Google reCAPTCHA using Tor within 5 minutes. It's painstaking for humans, while an AI has all the time it needs.