Something weird is happening with LLMs and chess

I don't understand why educated people expect that an LLM would be able to play chess at a decent level.

It has no idea about the quality of it's data. "Act like x" prompts are no substitute for actual reasoning and deterministic computation which clearly chess requires.

Right, at least as of the ~GPT3 model it was just "predict what you would see in a chess game", not "what would be the best move". So (IIRC) users noted that if you made bad move, then the model would also reply with bad moves because it pattern matched to bad games. (I anthropomorphized this as the model saying "oh, we're doing dumb-people-chess now, I can do that too!")