No you can make games with simple art or minimum art and it can turn to be great! You keep improving, its not you are not trying, you are trying you ar e making simple art with simple shapes! But when you use ai for very detailed images. It can feel unfair to other people who worked hard for their game. And by the way using ai all the time is not really a great thing. And using ai is not being very creative. Thats why many game jams ban ai. And they are right,