Depends on what the input to it is. There is an invincible AI for StreetFighter V that reads the other player's inputs from the network stream and simply chooses the perfect attack with which to counter. Much more interesting to me would be machine vision that can recognize what's happening on screen. I'd be fine with it getting frames via direct HDMI connection rather than with a camera and similarly inputting moves by sending USB packets down the wire, rather than physically pressing buttons.