You are making the mistake of confusing a mind with a human mind… a vastly different type of mind should not be expected to be good at everything we are good at, even if generally far more intelligent. I think people generally make the same mistake with discounting the more intelligent animals by focusing on their inability to act human, and ignoring or not noticing that they can do things we are incapable of- like a dog navigating a home in total darkness from scent alone- turning scents drifting in the air into visual/spacial type data is a complex task.

A human mind, for example is not sufficiently generally intelligent to convincing mimic even a fish mind- we cannot generally emulate minds structured differently either. Even an actual human mind with vastly different experiences- simulated perfectly in a computer or even just a regular person from a very different culture will fail your concept of the turing test, because our mind is shaped by our experiences.

Also, I think your conception of LLM limitations is mistaken. We don’t fully understand them in theory- but I think the way to think of LLMs is that they are a world model able to simulate almost any scenario if setup properly. They are not themselves a mind, but if sufficiently good, they will reliably simulate minds. Noam Chomsky published an article arguing how LLMs were incapable even in theory of doing things GPT4, which was released shortly after his article can do- showing that either his model of what they are, or of what is required for those tasks is mistaken .