You don't want a neural net for your game AI because it's behavior is unpredictable and therefore cannot be tested.
All of the issues AI companies have now times by a thousand because now the AI have access to a physical presence in the game world. It would cheat and find ways to know things about the game state that it's not supposed to know, or it would hide in a corner as far away from the player as possible because it's parameters is to avoid death, or some other unforeseen function of its instructions.