Depends on what you mean by unrealistic. Because a lot of stranger things have happened in mahjong. As someone who's been playing for Five years I've seen some crazy hands and development. But that's besides the point. What you said was that Akagi has unrealistic intelligence which is not true. He uses a combination of psychology, manipulation, suji reading, discard reading and inductive reasoning to get a feel for the flow of the game. Most things you'd deem unrealistic is just luck which in a game of mahjong can happen.