The strongest evidence offered that would make Gatsby seem contrived is that he constructs his entire premise of being. This is a contrived element. It is made up. It might be stretching to call it "fake" because Gatsby really believes its authenticity, but it is a manufactured condition of reality. Nick's words to this point help to illuminate this sense of being in the world: “The truth was that Gatsby of West Egg, Long Island, sprang from his Platonic conception of himself." In this "Platonic conception of himself," one sees the contrived nature of his existence. He makes everything up in order to satisfy a pursuit, what would be called, “a promise that the rock of the world was founded securely on a fairy's wing.” This helps to make Gatsby someone who is contrived.
With this in mind, it might be important to stress that Fitzgerald is seeking to make a statement about American society at the time. His genius might be that one can see it about all societies predicated upon shallow social advancement. In the end, everyone in the novel is, to a certain extent, contrived. Everyone is inauthentic. The world of both East and West Egg is predicated upon the idea that all social interactions are contrived, designed to make oneself more important and more impressive than they might be. Fitzgerald recognizes this hollowness that resonates underneath every party, ever embrace, and every potential interaction where people use others as a means to an end as opposed to ends in their own rights. Gatsby is at least somewhat authentic in his own creation. He does it to win over Daisy. That's it. He is unabashed about this and it it is for this reason that he is not as contrived and phony as others. Rather, he is authentic in why he does what he does and this makes him rather likable in a world where people are shown to be not very appealing at all.
The title character of The Great Gatsby by F. Scott Fitzgerald is Jay Gatsby. Both the reader and first-person narrator, Nick, meet him in person only later in the novel.
What is interesting about Gatsby is that he appears consciously elusive. He has lavish parties at his luxurious home, but seldom appears in person at these. When he does appear, hardly anybody notices him. On the first occasion when Nick meets him, for example, the narrator is not even aware that it is Gatsby himself.
Throughout the novel, it is as if there is a juxtaposition between the idea of Gatsby and the person he truly is. The idea of Gatsby can be said to be contrived by means of his parties and the rumors these fuel. Some speculate that he murdered somebody. Others wonder about the possibly shady origins of his wealth. Some also appear somewhat seduced by his generosity.
Nick, and by association the reader, soon begin to understand Gatsby as a person, however. Gatsby is a human being, as subject to heartbreak as the rest of humanity. This is proven by the tragedy in his past he refers to and his unrequited, almost school-boyish, love for Daisy. This is the real Gatsby. It is one he chooses to reveal to only a privileged few.
The image he presents to the world, however, is highly contrived. He does nothing to dispel the wild myths circulating about his true nature. In fact, part of the contrivance is encouraging these myths.
As such, Gatsby's public image is highly contrived. It is an image he consciously creates to hide the vulnerability that constitutes his true self, the Gatsby that can be wounded and disappointed.