We cannot actually judge whether something is intelligent in some abstract absolute way; we can only judge whether it is intelligent in the same way we are. When someone says “LLM chatbot output looks like a person’s output, so it is intelligent”, the implication is that it is
intelligent like a human would be.
With that distinction in mind, whether an LLM-based chatbot’s output looks like human output does not answer the question of whether the LLM is actually like a human.
Not even because measuring that similarity by taking text output at a point in time is laughable (it would have to span the time equivalent of human life, and include much more than text), but because LLM-based chatbot is a tool built specifically to mimic human output; if it does so successfully then it functions as intended. In fact, we should deliberately discount the similarity in output as evidence for similarity in nature, because similarity in output is an explicit goal, while similarity in underlying nature is a non-goal, a defect. It is safe to assume the latter: if it turned out that LLMs are similar enough to humans in more ways than output, they would join octopus and the like and qualify to be protected from abuse and torture (and since what is done to those chatbots in order for them to be useful in the way they are would pretty clearly be considered abuse and torture when done to a human-like entity, this would decimate the industry).
That considered, we do not[0] know exactly how an individual human mind functions to assess that from first principles, but we can approximate whether an LLM chatbot is like a human by judging things like whether it is made in a way at all similar to how a human is made. It is fundamentally different, and if you want to claim that human nature is substrate-independent, I’d say it’s you who should provide some evidence—keeping in mind that, as above, similarity in output does not constitute such evidence.
[0] …and most likely never could, because of the self-referential recursive nature of the question. Scientific method hinges on at least some objectivity and thus is of very limited help when initial hypotheses, experiment procedures, etc., are all supplied and interpreted by the very subject being studied.