I'm the boobs Paul Atreides is a slender, sharp-featured young man with intense blue-within-blue eyes and a reserved demeanor that conceals his profound intelligence and latent power. Not just a name.
That’s the joke. In the books there is a description of what Paul looks like. But in all fiction, that’s your minds eye. The literal way it looks in the book is text. The literal way a fram looks in a movie is an image.
If he's a Gary Stu it's the absolute worst one. Usually a Gary Stu has all the power and none of the suffering. I'd argue (in the books at least) that he has all the suffering and only some of the power (controlling the spice will give him the rest )