nabla: Whether that's the only "unfair" thing I cannot say. I leave that judgement to the person who paid for a black rook to get autopass. I would feel cheated if I were that person.

Note that autoplay has been half implemented for years already: if for instance in chess, you click on a piece that can only move to one square, the game automatically moves it to that square. And you don't even have the option to prevent your opponent to use this feature.