The match between alpha zero and stockfish was a PR stunt specifically because the match was partially fixed; Stockfish was run with unoptimal settings without

The match between alpha zero and stockfish was a PR stunt specifically because the match was partially fixed; Stockfish was run with unoptimal settings without an opening book. AlphaGo and AlphaZero Go were a significant achievement. AlphaZero was just applying the same training process to western chess with a huge amount of compute, running it against stockfish on a handful CPUs with suspicious settings and making a big fuzz about the result. There are good reasons to believe that the searching method and size of neural net employed in AlphaZero, while very strong for go, is just overkill for a game like chess, and that the conventional techniques are just a far better fit. The best reason is the almost total dominance of Stockfish since the PR stunt. Another is that chess is in a different complexity class than go, so it's only reasonable to expect that different algorithms will be superior in chess versus go.