I think a lot of people are fundamentally confused about what literary criticism is.
Some literary criticism is like TVTropes [content warning: will eat your entire afternoon]. TVTropes is trying to understand how stories work. Its strategy is to catalog all the recurring things that happen in stories, from Asian characters wearing conical straw hats to characters in love sharing an umbrella to a love triangle being resolved by the protagonist marrying both of them. Some literary criticism is intended to do a similar thing: for instance, Freytag’s pyramid, which you were probably taught about in elementary school, attempts to explain how most stories are structured. This is useful for writers: if your plot isn’t working and you don’t know what a ‘climax’ is, learning that stories are generally more interesting if they have a point of great tension can help you write better stories.
However, a lot of literary criticism– perhaps most– is not doing that, and if you think it does you will wind up very confused.
Consider Eve Sedgwick’s Between Men, a classic work of queer theory, which argues that much of nineteenth-century literature can be understood as being about homosocial desire and love, often reflected through both men’s putative desire for a female intermediary. If one assumes that the thesis of the book is something like “factually, a lot of nineteenth-century literature is about male-male bonding, and maybe if you put some male-male bonding in your book you should include a female intermediary they can both act like they’re in love with!”, one instantly falls into difficulties.
For instance, there’s the question beloved of high-school students everywhere, which is “did the author actually intend that?” Probably, one assumes, Dickens wasn’t thinking for even one second about the homophobia of empire while he was writing Edwin Drood. Of course, this isn’t a complete disproof: authors were writing rising and falling action for thousands of years before Freytag gave them names; presumably they were not intending to write rising and falling action. But it still feels intuitively that while climaxes, rising action, solving love triangles with polyamory, Asian characters wearing conical straw hats, and so on are all easily identifiable features of various books, the homophobia of empire is not, in fact, an easily identifiable feature of Edwin Drood. In fact, a reader would be perfectly justified to say that there was absolutely no homophobia of empire in Edwin Drood whatsoever.
Books are often assumed to be the product of their authors: the writer puts some words down on the page and the reader sees what they obviously mean and a story happens. The reader does not contribute much beyond basic literacy. But, in fact, the reader plays a huge role in the creative process. Some readers interpret Rorschach from Watchmen as a flawed yet admirable tragic hero who holds to his convictions even in the face of death; some readers interpret him as a Lawful Stupid sociopath who’s proof that moral absolutism cannot deal with the complexities of the real world. Some readers interpret Christian Grey as a sexy, kinky, masculine hero with a tragic past; some readers interpret him as an abuser grooming the naive and easily victimized Anastasia. Some readers interpret the violence against women in Game of Thrones as gratuitously signalling how edgy the writers are; others interpret it as a reflection of what women experience during war under patriarchy. The difference is what you bring to the story: your worldview, your preconceptions, the books you’ve read in the past, whether that one particular character happens to remind you of your horrible abusive ex-boyfriend.
Now, some people feel that their interpretations of texts are objectively correct: by God, Christian Grey really is an abuser, and if you disagree then you are wrong and probably an abuse apologist. But I’m not sure what the ‘real meaning’ of the text even means. If Christian Grey ‘really is’ an abuser, what predictions does that allow us to make? How is anything about the world different if Grey is an abuser, compared to if he isn’t? If the answer is (as seems likely) “nothing”, then it doesn’t really mean much to say that one meaning is objectively correct.
Some people care a lot about authorial intent: if the author intended Grey to be a kinky, sexy, masculine hero, then he is a kinky, sexy, masculine hero, and none of your abuse checklists have anything to say about it. This seems silly, though. Tommy Wiseau appears to interpret The Room as a serious drama; everyone else interprets it as a so-bad-it’s-good comedy. I don’t think that everyone who isn’t Tommy Wiseau is making a mistake.
The Eve Sedgwick kind of literary criticism, I think, is not empiricism: it’s not trying to make predictions about what features stories will have or what characteristics will make readers like stories or whatever. It’s art. It’s a very unusual kind of art that takes other art as its raw material. It’s the task of the reader– interpreting a text, creating a story out of black lines on a page– taken to its highest form. This kind of literary criticism is about making interpretations that are more interesting than most people’s, that make you go “oh! that’s clever!”, that enrich your own rereading of the text and make it more interesting than it previously was. Asking whether or not it’s ‘true’ is like asking whether or not a painting is ‘true’.
Between Men is not TVTropes. It’s not trying to be TVTropes. It’s meta. Does the text actually say that Steve and Bucky are dating? Not really. Does it improve my experience of Civil War to read thousand-word close readings about what exactly Bucky was thinking when he clenched his jaw muscle? You bet your ass.
Of course, this sort of literary criticism should be justified in the text. You cannot say “Hamlet is a Klingon!” without providing some sort of reason in the text of Hamlet for why he ought to be a Klingon– because “Hamlet is a Klingon” is not an interpretation anyone would normally make. You have to lead the reader to be able to see for themselves that Hamlet is a Klingon, to have “wow, this is really something a Klingon would say” wandering across their mind during random scenes– or, for that matter, to see that Steve and Bucky are dating, Tennyson is hella gay, and Edwin Drood involves the homophobia of empire.