Humans have more variability and "edge". If a person is passionately arguing for some point of view (perhaps somewhat outside the usual), it signals to me that they probably thought about this and it is a distillation of a long thought process and real-life experience. One could say that the logical argument should stand alone, but reality doesn't work that way. There are many things you have to implicitly trust and believe when you read. Of course lying and bullshitting already existed before ("nobody knows you're a dog" etc etc). But LLMs will really eloquently defend X, not X, X*0.5 and anything inbetween. There is no information content in it, it doesn't refer to an actual human life experience and opinion that someone wants to stand behind. It just means that someone made the LLM output a thing.