These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Is Gatsby a manipulative and scheming stalker; or a broken man who idealizes Daisy, and pursues that idealized version of her?
Jordan Baker; just as bad as everyone else, or a product of the times (explaining her cheating and lying)? Or is she just a cynical person from a wealthy background who isn't really friends with the Buchanans, and just snarks behind their backs (the 1974 version seems to support this theory)?
Tom Buchanan: a brutish, racist abuser, or just a jealous man in a loveless marriage?
Daisy Buchanan: shallow and flighty? Materialistic and manipulative? Or a Broken Bird trapped in a marriage with a man who possibly abuses her?
Nick: he spends the entire book talking about how kind and decent he is, how he doesn't judge people, and engaging in tragic-hero-worship of Gatsby, but when he knows someone's out to kill him (and is in a position to at least try to stop the death of this man he supposedly admires so much), he just stands by and lets it happen. Honest, decent Midwesterner, or just as much of a hypocrite as everyone else in the book? Not to mention being aware of the various affairs transpiring around him, but choosing to keep his mouth shut.
Ending Fatigue: To a certain extent, although it could also be "starting fatigue". The plot moves very slowly until all of the characters go to New York around chapter seven or eight, at which point it speeds up significantly, then slows down again when they leave.
Harsher in Hindsight: Meyer Wolfsheim, the Jewish mobster, works in an office labeled "The Swastika Holding Company." The book was written in the 20s. Oh boy.
Interestingly, the book was not well known until it was republished and hit the peak of its popularity immediately after WWII.
Not to mention Nick referring to the Murder Suicide using the term 'holocaust'.
Headscratchers: Nick mentions at the beginning of the book that his family is considered to be quite prominent and well-to-do in the Midwest. Yet when asked why he won't marry the girl he left in the Midwest at Tom and Daisy's, he says that the rumour isn't true because he's too poor.
Ho Yay: Nick seems quite... obsessed with Gatsby, pretty much all the way through the novel. "There was something gorgeous about him"? Not to mention the Nick/McKee scene at the end of chapter 2.
Albeit it should be noted that much of this is the result of language drift since the novel was written - as per the example above, which uses 'gorgeous' in its original sense of 'splendid' and/or 'showy'.
Look at Nick's excuse for coming east, mentioned in his first meeting with the Buchanans. He used to spend a lot of time with a girl as Platonic Life Partners, but everyone drew the wrong impression and started expecting him to propose, which he didn't want to do. Why not? The novel never answers, leaving readers to decide whether they were Like Brother and Sister or The Beard.
The video game drops all subtlety, having Nick as the hero and, most importantly, Gatsby as the Distressed Dude Nick has to save.
Hype Backlash: Many classes at the college and high school level take offense at the 'definitive American novel' title based on the stupidity of its characters and the soap opera nature of its plot. Just as many argue that Fitzgerald wanted to attack East Coast Rich Bitch lifestyle with a thinly veiled Take That.
Love It or Hate It: The book is considered to be one of the best books in the English language to some. Others consider it to be utterly boring and pretentious. Unfortunately, a lot of this is because this book is on many high school reading lists, forcing many a teenager to unwillingly read a book intended for an audience many years older than them.
Misaimed Fandom: The story viciously and repeatedly lampoons rich, upper-class American society. Guess what sort of parties are Great Gatsby-themed? (Ex: Greek, "The Great Cappie")
Also, those who feel inspired by the book to pursue their dreams of money and social status, ignoring how Gatsby amassed his wealth through criminal activity and the way it turns out that his image of Daisy, his real goal, was naught but an idealized dream.
Similarly, Lauren Conrad continually points out how much she loves the book because she's "obsessed with the style of the 20s!".
People hate on Daisy for rejecting Gatsby, when there are much worse characters than her in the book. Like for example, Tom, who beats women, cheats on his wife, and is actually responsible for Gatsby's death.
Tear Jerker: Maybe not on a first reading, but definitely on a second reading or when you watch one of the adaptations when you realize that everything Gatsby did for Daisy was for naught.
"Gatsby believed in the green light...."
Values Dissonance: Tom Buchanan's admiration of racist books, for starters. Then later, Tom bashing the idea of interracial marriage. Either invoked intentionally to comment on the nature of times, or to establish further that Tom is a jackass. (Daisy gives token agreement but nothing more. Nick remains silent, as an Audience Surrogate ought.)
Vindicated by History: The novel was forgotten during the Great Depression and WWII, and didn't sell that well when it was first released.
On that note, letting a director known for his flashy, indulgent style adapt a novel condemning that very style. Some think it's a good idea, others think it's a horrible one. Some might argue it's Baz's method of a deconstruction.
Critical Dissonance: Critics gave the movie mixed reviews with a 50% rating in Rotten Tomatoes. However, the movie was doing well in the box office, landing at No.2 when it first came out. Its critical reviewers' score also sits at about 50%, whereas the viewers' score is over 80%.
Filter's Cover Song of "Happy Together" by The Turtles which was used in the second trailer. Sadly, it's not included in the soundtrack since this song is first used for the OST of the 2009 film, The Stepfather.
"Young and Beautiful" by Lana Del Rey couples as a Tear Jerker. Especially when considering it's written from Daisy's perspective.
When we see why Daisy didn't wait for Gatsby: Literally hours before Daisy's wedding to Tom, which she agreed to because she thought Jay was dead or abandoned her, she got a letter from him, reaffirming his love for her and asking her to wait for him until he became wealthy. She immediately has an emotional breakdown, ripping off her necklace (an engagement gift from Tom) and screaming at her family to "tell them Daisy changed her mind!". Next we see of her, she's sitting in the bath, having a huge bout of Heroic BSOD, and breaking up the pieces of the letter into the water while her family tries to stall for time. She then marries Tom, and you can just see how fake her smile is.
YMMV, but when Myrtle dies. She was kind of a bitch to Wilson, but she seemed to genuinely believe that Tom would be able to save her from her situation, especially as we see Wilson shouting at her in the upstairs bedroom, with her staring desperately outside with teary eyes and a cut on her forehead.