Rarely have the Oscars seen such a dead cert. If you fancy La La Land for best picture, the most attractive odds you will get are 9-2 on. The film is also nominated in another 13 categories, tying with Titanic and All About Eve for most ever nods. It has already snagged a record-breaking seven Golden Globes, and five Baftas.

Critics have been equally charmed. In Britain, the coveted five stars have been bestowed not just by the Sun, the Mirror and Metro, but also by the Guardian, the Times and the Telegraph. Audiences have followed suit. The film has taken more than 10 times its $30m (£24m) budget at the box office.

In such circumstances, you would expect a bit of a backlash, and a La La Land insurgency has duly kicked off. The male lead, Ryan Gosling’s Sebastian, has been indicted for boorishness and insensitivity. When he is not whitesplaining jazz, he is mansplaining it to Emma Stone’s Mia. Both characters have been thought shallow, and chemistry between them has been found lacking. Technique has also been faulted. Gosling and Stone are no Fred and Ginger in the hoofing stakes, and their “reedy voices” have disappointed. For some, the narrative sags and the plot fails to convince. Just why do Seb and Mia break up? A temporary separation doesn’t have to destroy a relationship. Then there is the counterfactual ending. What is it supposed to mean? That they should have stayed together? When they could have, but didn’t and appeared content with the alternative paths they had chosen?

Naysayers have made yet more sweeping charges. La La Land has been branded feeble, dull, flat, humourless, bloodless and unengaging. It has been called a “sort-of-musical, sort-of-movie-about-jazz, sort-of-underdog tale” that is “disappointingly mediocre”.

In fact, these reactions can be traced to a deeper deficiency: the Oscar favourite is a fake movie. Poke your finger through the sugary icing and you find no cake beneath – no heart, no soul, no joy, no warmth, no wonder.

To create the illusion of charm, the film relies not on intrinsic strengths but on external trappings. There is the glamour of its beauteous stars, and recollections of their past, more stirring, pairings. There is the tinselly glitz of Hollywood and the Californian sunshine. Above all, La La Land depends on parasitising other, better films marinated in the nectar of nostalgia.

When Gosling hangs from a lamp-post, it is to tell you this is Singing in the Rain. West Side Story, Funny Face, The Young Girls of Rochefort, Shall We Dance, The Umbrellas of Cherbourg and plenty of others are similarly appropriated. La La Land wants you to believe that it shares the joy, humour, tragedy and humanity of such celluloid treasures. It doesn’t.

Most of the films referenced are romances. They celebrate love and life. La La Land does the opposite. Its principals don’t find meaning in each other. For the most part, their relationship is glossed over in montage. Their heart-to-hearts are rendered in stilted cliche.

They get together when their careers are failing, and spend their time sharing notes. Once they have co-mentored themselves on to the road to personal advancement, they ditch each other like a rocket’s blast-off section.

The aspirations they pursue instead of each other involve neither duty nor philanthropy, but only self-realisation. City of stars, are you shining just for me? You damn well ought to be, because I’m worth it.

Mia points out the window from which Bogart and Bergman gazed in Casablanca. That film was about sacrifice for love. In La La Land, love is sacrificed for self. Once this becomes clear, La La Land’s disparate vagaries start to explain themselves. Of course, its characters are humourless and insensitive: narcissists usually are. They can’t be rich and complex, because self-obsessives aren’t.

Facebook Twitter Pinterest For this role, Gosling learned to play the piano in three months. If it is that easy, we can all imagine uploading ourselves into the ultimate Instagram ego trip. Photograph: Dale Robinette/AP

Mia is a cipher because she is just the prisoner of ambition. Seb sees himself as a heroic champion of art, but he is more of a nerd than a musician. For him, jazz is mainly fodder for his vanity and pomposity. Real enthusiasts consider that purists such as him are holding back the genre, not rescuing it from ruin.

The puzzles of the narrative also begin to resolve themselves. The reason not much seems to happen is that egotists are not deeply conflicted and don’t go in for much interaction with others. When Seb arrives to pick up Mia, he blasts his car horn rather than ringing the doorbell. Never mind the neighbours; it’s only Seb who counts. When Mia is looking for Seb in a cinema audience, she stands in front of the screen and blocks the picture. Of course. She matters; the other filmgoers don’t.

We can now see why these sweethearts separate. On their last night together they pledge eternal love; but they also promise to follow their dreams. For them, the latter was bound to trump the former: self-worship brooks no distractions. If, at the end, Seb seems a little lonely and Mia seems a little bored, no matter. Their final smiles indicate that both have attained what really matters: self-satisfaction.

Still, La La Land is a film for our time. With our self-nurturing, self-promotion, clicktivism, Twitterstorms, sexts and selfies, we are all narcissists now. This being so, many of us would kill to get into Seb or Mia’s shoes. The Strictly and X Factor level of the film’s performances hints that we might. To prepare for this role, Gosling picked up piano-playing in a mere three months. If it is that easy, and you don’t have to be very good, we can all imagine uploading ourselves into the ultimate Instagram ego trip.

Nonetheless, our descent into solipsism still carries with it lingering disquiet. La La Land helps us put this aside by spangling self-love with stardust. This may be a neat conjuring trick; whether it entitles the film to cinema’s highest honour is another question.

It is easy to see why the Academy’s voters have embraced La La Land. Many of them will have followed a path all too similar to Seb and Mia’s. Seeing their life-choices vindicated by the witchcraft of their trade must have been something of a comfort. All the same, the best picture winners that stick in the memory, such as Schindler’s List, Gandhi, Chariots of Fire and Titanic, tend to extol humanity’s better nature, not its shortcomings.

This time round there are also films among La La Land’s doomed rivals that could make us proud of our species. Moonlight deals with love. Manchester by the Sea offers contrition. Arrival honours inquiry. Hacksaw Ridge celebrates selflessness. Any of these would be a worthier winner than Damien Chazelle’s tawdry and dispiriting confection. La La Land’s victory on Sunday night will tell us something about our era. But it will be no triumph for film-makers, filmgoers or film.