Jotaro’s counterattack against Kira is honestly one of the reasons I don’t really get why he’s so often called a Mary Sue/Marty Stu. While Jotaro does have honestly very broken powers and a “cool” (for lack of a better word) personality to him, he’s also affected by the other people around him, as opposed to a Sue or a Stu, who only have other characters around them to make them look better. Jotaro beating down Kira isn’t about making him look good and more the best way for the story to get Jotaro, who’s an emotionally retarded fencepost, to say, “I have already lost enough people to some lunatic who thinks that he can just get away with whatever the fuck he wants. I’m not losing this one, too.” That’s just my two cents, of course.