> A consequence of this state of affairs is that an LLM will continue to engage in a “conversation” comprised of nonsense long past the point where a human would have abandoned the discussion as pointless.
I think the author is falling into the trap of thinking that something can't be more than the sum of its parts. As well, 'merely a math model of its training data' is trivializing the fact that training data is practically the entire stored text output of humankind and the math, if done by a person with a calculator, would take thousands of years to complete.
Perhaps the LLM is continuing to communicate with the bot not because it is unable to comprehend what is gibberish and what isn't by some inherent nature of the LLM, but because it is trained to be helpful and to not judge if a conversation is 'useless' or not, but to try and communicate regardless.