People are more than one dimensional. That he cursed doesn't mean his PP persona was not a genuine part of his. And if so then why be ashamed of it? There is nothing wrong with not being like everyone else. In fact, what is really "a normal man"? Is there even such a thing? And if there is is that a positive thing at all? Cursing makes "a normal man"? Should we desire MJ, who was an exceptional artist with an exceptional world view and exceptional personality, be like a "normal man"? Would that really be a positive thing? Artists are rarely "normal", whatever that means. (Flashback from "Ghosts" where the inhabitants of "Normal Valley" attack him for being different. Michael wasn't and maybe did not even want to be a part of "Normal Valley".)
Of course, PP is just one dimension of his personality and it is equally wrong to portray him as this one-dimensional PP figure. But it was there. Genuinely. It wasn't like he acted this child-like way in public for image, while he was a completely different man in private. That he cursed does not change that. Nor that he could be serious and business minded when needed. He also had his childlike side and there is nothing wrong with that. Michael embraced it and was not ashamed of it at all. And he should not have. That's just who he was.