LLM's were terrible at chess last year. Today, they can't beat stockfish but they can play competitively with the top 2% of chess players. Next year, who knows.
Look at the “legal %” field on that chart. That’s utter trash even counting per move vs games without errors. Further they outperform vs bots who stick to main lines more than normal players, actual performance vs humans means both lower ELO and more errors.
Note: * = Anchor player (fixed rating, used for calibration)