A human can learn and understand the rules, an LLM never could. LLMs have famously been incapable of beating humans in chess, a seemingly simple thing to learn, because LLMs can't learn - they just predict the next word and that isn't helpful in solving actual problems, or playing simple games.

Actually general-purpose LLMs are pretty decent at playing chess games they haven't seen before: https://maxim-saplin.github.io/llm_chess/