Identity politics is coming in for a kicking at present, with many of the boots predictably attached to the feet of those who oppose the focus by the left on the struggles of minorities, women and the LGBT community. Identity politics is thus a convenient scapegoat for the mercurial rise of the populist right. Its critics are apt to play a game of victim blaming.

A woman who speaks up too forcefully against sexism, or a black man who decides the best way to fight back against police violence is to protest, are apparently overreaching themselves and should pipe down. We would apparently never be in this mess had they known their place.

Yet to paraphrase Orwell, there are problems with mainstream identity politics even if it is a bellicose section of the white and male right which happen to be pointing it out. The problem is not of course that which is usually identified by its critics: some people really do need diversity and feminism 'rubbed in their faces' – that thing frightened commentators seem to fear the most.

No, the issue is the class-blind form that contemporary identity politics seems to take. For many of the liberals who espouse it, identity politics has become about tuning up elites and making them 'representative' rather than abolishing them altogether.

This was in many respects an entirely predictable outcome. From Che Guevara zippo lighters to the 'pink pound', capitalism is incredibly good at co-opting things which start off as rebellions against it. A company with a highly paid boardroom that is diverse and 'representative' is certainly an improvement on the white, male and stale state of affairs which went before it. But it is hardly a threat to the status quo.

A new report from the Resolution Foundation on agency workers should make clear to those on the left that the elitist form which identity politics commonly takes is not enough. The report itself presents damning evidence that many of us are being shafted by the balance of employment power in Britain today.

A full-time agency worker gets on average £430 less than a permanent member of staff a year for doing the same job. This is particularly troubling when the number of agency workers is set to reach one million by 2020. As well as taking a hit on pay, agency workers lose out on benefits like sick pay and parental leave and are easier for capricious bosses to sack.

With Theresa May's government apparently intent on turning Brexit Britain into a North Atlantic free market paradise, and with a Labour Party flagging badly in the polls, it seems inevitable that this race to the bottom in terms of employment practice will continue. Freedom, as interpreted by the Brexiteers, seems to mean little more than the freedom for someone else to toil away in precarious jobs for poverty wages with few rights.

Yet something else in the report stands out in terms of just who is being hit the hardest by the rise in agency work. Clue: it isn't white men. Women accounted for 85 per cent of the growth in temporary agency workers, while ethnic minorities were three times more likely to be agency workers than their white counterparts.

This ought to bury the ubiquitous notion of a uniquely beleaguered 'white working class' man. Working class men are certainly suffering because of the forces aligned against their class. However, the same forces are being brought to bear even more fiercely on other groups. The affluent liberal politics which comes cloaked in a snobbish disdain for the working class is a dead end. But so is a politics of a working class defined exclusively by its masculinity and whiteness.

As with old economistic strands of left-wing thought, identity politics is infuriating when it becomes overly deterministic. Wallet size, skin colour, gender and sexuality influence rather than determine a person's ideas about the world. But a far bigger problem is the tokenistic and elitist form which identity politics usually seems to take.

Beyond opposition to racism, an Indian businessman from Manchester who heads up a chain of low-paying warehouses does not share the same interests as a black teenager from Peckham who toils away in them. In fact, this sort of class-blind identity politics, which talks knowingly of a homogenous 'minority community' and could not comprehend why working class women failed to back Hillary Clinton, does a disservice to many of the people it claims to champion.

Those who are genuinely interested in the fate of the working class cannot restrict their concern to a white and male subsection of it. But nor can the purveyors of identity politics assume that equality for women and ethnic minorities means little more than a diverse FTSE 100. As today's damning report makes clear, many of those who must confront racism and sexism in their everyday lives are also the prisoners of their class.

James Bloodworth is former editor of Left Foot Forward, one of the UK's top political blogs, and the author of The Myth of Meritocracy.