Neill Blomkamp's sci-fi adventure has a lot to tell us about poverty and privilege – but are we ready to listen?

Box office chart-topper Elysium may be set in 2154, but according to its director it's about the here and now. "The movie's meant to be an allegory," says Neill Blomkamp. His film's message: the material inequality that pervades our world today is "an outrage".

Like other recent movies on this topic, from In Time to The Hunger Games, Elysium has struck a chord. Inequality of wealth and income has reached startling proportions, not just in the US, where Elysium is set, or in South Africa, where Blomkamp is from, but also in Britain. Hence, big-screen cries of outrage such as Blomkamp's elicit plenty of hurrahs. At Sundance 2013, for example, Inequality for All, a trenchant documentary presented by Robert Reich, was a surprise hit.

Blomkamp seems to have brooded long on his weighty theme. Doubtless he expects his film to provoke further musing. The story (warning: spoilers ahead) sees a celestially gated, privileged community penetrated by intruders from planet Earth, on which the majority toil amid squalor and woe. With the click of a mouse, the insurgents bestow instant equality on their fellow proles beneath. But Blomkamp's film has little in common with Eisenstein's Strike, Widerberg's Joe Hill, Spartacus, Lindsay Anderson's If or even Made in Dagenham.

This time, it isn't an uprising of the oppressed that brings about change. The hero, Matt Damon's Max, is out to save his own skin. His partner in the venture, Wagner Moura's Spider, is in it for the money. Even their saintly companion, Alice Braga's Frey, is after a cure for her daughter's leukaemia, not universal parity. Revolution proves incidental.

Blomkamp doesn't believe disgust about inequality is part of our makeup. "You'd literally have to change the human genome to stop wealth discrepancy," he said in a recent interview. He has a point. In the real world, victims, not just fat cats, are reluctant to do much about inequity.

In 2154, Elysium's drudges have little opportunity for rebellion: brutal robots police their every move. Today, on the other hand, we have plenty of scope to rise up, but still we don't. In 2003, the prospect of the Iraq war provoked a million-strong march through London; but the most the 99% have managed against the 1% was a brief encampment outside St Paul's. When riots broke out two years ago, the thin blue line of our oppressor snapped under the strain. Instead of seizing the chance to overrun One Hyde Park, we used it to nick a few phones and trainers.

It's easy to see why the well-heeled cherish the status quo, but it is less obvious why the rest of us seem so ready to stand for it. Never Let Me Go, Mark Romanek's film about a group of clones created for their body parts, highlighted the acquiescence that exploitation can create. But while today's inequality provokes plenty of griping, it doesn't inspire much action.

Deep down, perhaps we just don't care. One logical explanation is that we've bought the propaganda of our rulers. We are told that inequality is essential; without the prospect of advantage, people wouldn't take risks to create the wealth on which we all depend. But we don't seem to buy this line.

It is the wealth creators in finance and business whose greed most offends us. We don't mind the rapacity of those we happen to like. If film stars or footballers were paid less, ticket prices could be lower, but their fans don't seem to object to the cupidity of their heroes. When Adele moaned about paying her taxes, people grumbled, but still bought her music.

Americans are said to approve of inequality because, being optimistic types, they think that one day they too will secure a place among the elite. In Elysium, the young Max makes a solemn pledge to his fellow orphan, Frey: it's not that he'll liberate their subject race by laying low its masters; it's that he'll somehow propel the two of them up the ladder.

Europeans are too glum to indulge such hopes, but perhaps our feudal past yields its own impulse for compliance. Maybe we accept inequality as part of the natural order. In movies, we often portray ourselves as downtrodden, whereas American films celebrate the lifestyle of the rich. Favourable views of the poor, such as Ken Loach's, can make the impecunious life appear cosier than that of the miserably moneyed.

We like to believe that the rich aren't happy, that they are anxious, jealous and beset with strife. For decades, the Easterlin Paradox assured us that wealth beyond a certain amount brought no added bliss. Sadly, recent research makes this look doubtful. It seems that, after all, the richer you get, the better you like it.

Of course, equality has its perils. Levelling the playing field may sound attractive, but would require everyone except the most disadvantaged to makes sacrifices. This might be why we welcome it in theory but not so much in practice.

In Blomkamp's film, the teeming masses of humanity are suddenly eligible for Elysium's entire healthcare system. We aren't shown what impact this has on existing patients, but it's safe to assume there is a slip in standards. Spaceships that ferry illegal immigrants to Elysium are shot down. Today, while no one would actually sink a boat, not even the most progressive citizens of rich countries want their borders thrown open to the wretched of the world.

Elysium's political leaders, like our own, want to appear compassionate. Compared with them, Jodie Foster's brutal defence chief sounds harsh, but what she says makes sense: unless the privileged protect themselves from the just demands of the poor, they cannot expect to survive.

So, for all but the destitute, inequality turns out to be indispensable. It preserves us from expropriation while bathing us in a congenial blend of resentment and self-righteousness. What's not to like?

More on Elysium

• Peter Bradshaw's review

• Neill Blomkamp video interview

• Neill Blomkamp: 'You'd have to change the human genome to stop wealth discrepancy'