This post contains spoilers for Ready Player One.
It's set in a near future quasi-dystopia, where Earth is ruined. However a genius, Halliday, created a virtual reality system which everyone uses. When Halliday died, he leaves his fortune and control of the virtual world as a treasure hunt. Halliday was fixated on the 1980s, so all the clues revolve around popular United States culture from that time period.
It's essentially a Grail Quest story, as the hero, Wade Watts, faces successive trials in his quest for the treasure. The villain is the standard over-the-top evil corporation.
Part of my antipathy is that I don't have much respect for 1980s popular culture. It's decent enough, I suppose, but the idea of a generation committing it to memory is rather horrifying to me.
Ernest Cline is obviously liberal, and this has an odd habit of bleeding through in unexpected ways. For example, though most of the book is online using avatars, when the good guys meet up, it turns out they meet all the standard diversity checkmarks. Although it did amuse me that you could tell this written before 2015, as there are no transgender characters, the current cause du jour. Especially as it would be really easy to fit one in, what with the difference between avatar and person.
The attitude towards government and corporations is weird. Corporations are so powerful that slavery or indentured servitude has come back. However, government is powerful enough that medical privacy laws are absolutely inviolate. Perhaps it was just the necessary positions needed for the plot, but I found it jarring.
The tech in the story is also odd. It often feels more like magic than anything else. It features avatar perma-death, which is unusual. Personally, I think Cline over-values cleverness and discounts brute force, which makes the tech feel a bit off to me. Simple brute force is very powerful when the computer is fast enough.
All this is pretty minor, and more amusing than anything else. The real problem, though, is that Cline misses the point of Grail Quest stories, and it ends up making Wade's quest feel arbitrary and hollow.
In a traditional Grail Quest, the hero's virtues are tested by the trials. Virtues like kindness, resolve, and courage. The quest in this book does not test any of those. Certainly Wade displays some of those characteristics during his adventure. Especially in the middle section, when he finally does something worthy of being a hero. But this feels kind of coincidental to the trials, and not required. If you look at Willy Wonka, for example, Charlie wins because he is a good kid, and resists the temptations of the trials.
Instead, the trials pretty much test Wade's knowledge of 1980s trivia and ability to play videogames. I was really hoping that the final trial would require Wade breaking with Halliday's obsessions, demonstrating independence of thought, the student surpassing the master. Instead it was yet another videogame.
Even the deus ex machina aren't quite right. There are two points in the story where Wade is saved or successful because of arbitrary objects in his possession. The first he just mentions that he bought it a few months ago when it comes time to use it, and the second he got because he decided to get the max score in a random video game he finds while searching for a clue. Now, Grail quests have deus ex machina objects, but they're sort of earned. For example, the hero will save a fox from a trap early in the story, but later when the hero is captured by bandits, the fox will reappear and chew through the ropes binding him. The hero's virtue leads to an unexpected payoff. But Wade demonstrates no virtue in getting these objects which save him.
Since the trials evolve entirely around trivia and videogame skill, it is very arbitrary as to how fast each side solves clues. There's no reason that the evil company takes so long to solve the last clue, while the heroes remember it from an old song almost instantly, other than the plot demands it.
Ultimately though, Ready Player One says that Wade Watts was worthy of being the Philosopher God-King of the virtual universe because he could recite Monty Python and the Holy Grail by heart, and play a perfect game of Pac-Man. You'll forgive me if I don't think that is enough.