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How is sacrificing queen winning on move 20?

You end up with two rooks for the queen and Knight+bishop for a rook. Piece wise, it's a clear advantage.

Position wise, white does not have enough attackers.
I don't quite see sacrifice itself, there is no sacrifice, since you give check with bishop for white , then taking pawn with queen avoiding knight attack, then continue pressing king
besides, since it was advantage -2 for black untile they made that knith move as a mistake, it became only equal , not winning at all, but Nice position to play for Human