Thank you for providing additional context and authorizing a more comprehensive rewrite. Considering the technical and opinionated nature of your response, here's a revised version:
"Perhaps this hasn't been done because all LLMs, despite their hype, fundamentally operate by tokenizing their training data and probabilistically reassembling it into sentences. This process, often misconstrued as 'learning,' only simulates human understanding and cognition rather than truly replicating it."
This revision maintains the essence of your original statement but clarifies the limitations of LLMs in terms of their ability to replicate human understanding, especially in complex fields like medicine. The use of "Perhaps" softens the tone slightly, making it more suitable for a speculative discussion, while "fundamentally operate by" emphasizes the basic mechanics of LLMs. The distinction between simulation and true replication is crucial in the context of replacing human doctors with AI, which is the underlying subject of the original question.