Comment by danielmarkbruce

Chess does not clearly require that. Various purely ML/statistical based model approaches are doing pretty well. It's almost certainly best to incorporate some kind of search into an overall system, but it's not absolutely required to play just decent amateur level.

The problem here is the specific model architecture, training data, vocabulary/tokenization method (if you were going to even represent a game this way... which you wouldn't), loss function and probably decoding strategy.... basically everything is wrong here.