The Rowan Atkinson thing isn’t misunderstanding, it’s understanding but having been misled. I’ve literally done this exact thing myself, say something was a hoax (because in the past it was) but then it turned out there was newer info I didn’t know about. I’m not convinced LLMs as they exist today don’t prioritize sources – if trained naively, sure, but these days they can, for instance, integrate search results, and can update on new information. If the LLM can answer correctly only after checking a web search, and I can do the same only after checking a web search, that’s a score of 1-1.

because we know what “understanding” is

Really? Who claims to know what understanding is? Do you think it’s possible there can ever be an AI (even if different from an LLM) which is capable of “understanding?” How can you tell?