Oscars 2015: The films nominated are no longer the top-grossers

It's that time of year again, when the Hollywood establishment prepares to pin the tail on the donkey, a process also known as choosing the year's Best Picture. Always an imprecise science, the allocation of shiny statuettes seems ever sillier as the gap between Golden Globe or Oscar nominees and the movie market steadily widens.

In the 1970s, before the blockbuster era, seven out of 10 Best Picture winners were among the decade's 50 highest-grossing films. By the 2000s, that number was down to just one: the last Lord of The Rings, which triumphed at the box-office and at the 2004 Oscars. Since then, no Best Picture has broken into the annual box-office top 10.

It used to be simple: Rocky, One Flew Over the Cuckoo's Nest and The Godfather parts one and two were all Oscar winners and commercial hits. But nowadays the films with accolades are rarely those with the greatest popular heft. So, how to identify the year's defining film?

Judged by the bottom line alone, the most important movie of 2014 was Transformers: Age of Extinction, which took in more than $1bn (£660m) worldwide. But the year's biggest film at the domestic US box-office was Guardians of the Galaxy. The success of Guardians gave its studio, Marvel, the confidence to unveil a slate of superhero movies stretching to the end of the decade, thus ensuring no Best Picture will also be the year's top-grosser until at least 2020.

For that reason, perhaps the film of the year was not Guardians, but Birdman, an Oscar contender that eyes the superhero genre with undisguised disdain. Mexican director Alejandro Gonzalez Inarritu's brilliant black comedy stars Michael Keaton, formerly Batman, as the washed-up faded star of the fictional superhero franchise, Birdman. As he pursues artistic credibility on Broadway, Keaton's character is told: "Popularity is the slutty little cousin of prestige."

No film comes laden with more prestige this awards season than Selma, a historical drama depicting the 1965 voting-rights marches in Alabama. And in terms of sheer timeliness, no film could have arrived at a more appropriate moment, with the relationship between the authorities and the African-American community under visible strain again, half a century since the Civil Rights Act.

Awards season would not be complete without a controversy over a film or films' historical accuracy or lack thereof. In a Washington Post opinion piece published on Boxing Day, Joseph Califano, a former aide to LBJ, complained that the late president had been grievously misrepresented by Selma, which he suggested ought to be "ruled out" at awards season.

In a separate fuss, David Oyelowo and Carmen Ejogo, the British actors who play Martin Luther King and his wife Coretta in Selma, were last week snubbed by Bafta – lending credence to the theory that black British actors are more appreciated in the United States than at home. But let's accentuate the positive: Selma helmer Ava DuVernay is the first black woman nominated for Best Director at the Golden Globes, and will likely repeat the feat at the Oscars.

By far the best reviewed film of the year was Boyhood, Richard Linklater's quietly ground-breaking portrait of Texas adolescence, filmed sporadically over the course of 12 years. Resolutely undramatic, it nonetheless gripped audiences for the entirety of its two-and-three-quarter-hour running time. With its modest $4m budget, Boyhood has been pitched to the public (and the Academy) as an underdog, but remains the odds-on favourite to take home the Best Picture Oscar.

And yet, in terms of its impact in Hollywood and beyond, the film of the year was a dumbly funny, frat-boy stoner comedy, which earned a limited release last month and might have been largely forgotten by now – if not for the fact that it was set in North Korea. The Interview featured its co-director, Seth Rogen, along with James Franco as two clueless US television journalists, who secure an interview with Kim Jong-un and are then enlisted by the CIA to assassinate him. The film appears to have prompted the recent devastating cyber attack on Sony Pictures, which the FBI believes was carried out by, or at the behest of, the Pyongyang regime.

The hack brought a major studio to its knees and dented several high-profile Hollywood relationships, somehow turning The Interview into a diplomatic hot potato and a free speech cause célèbre. Most troubling of all, the episode will cause Sony and other movie studios to think twice before they give a green light to anything remotely controversial again. At least one other North Korea-themed project has already been canned in the wake of the hack.

Hollywood is no stranger to self-censorship: several recent blockbusters were altered so as not to offend the censors who control China's booming movie market. In making Transformers: Age of Extinction, Paramount collaborated with China Movie Channel, a production company that is owned and operated by the Chinese state. The film was shot largely on location in Beijing and Hong Kong and includes several prominent Chinese product placements.

It is now the highest grossing film of all time in China. The Interview has so far made a paltry $5.3m in cinemas. Pandering earned Hollywood its biggest pay cheque of the year. Taking a risk led to disaster. You see where this is going, don't you?