This year’s Cannes film festival staged a clash that might have passed viewers by: namely, a fight between good old-fashioned social realism and a new, politically conscious cinema – one also concerned with probing sociopolitical injustice, but in a looser, more refracted way.

In the left corner: Ken Loach, twice a winner of the Palme d’Or, with Sorry We Missed You, and the documentarian Lech Kowalski, promoting Blow It to Bits, a film about sustained industrial action taken by French auto workers.

In contrast to these (but also in the left corner) are Mati Diop, whose Atlantique delves into the supernatural to rail against exploitation; Juris Kursietis, who uses religious imagery to address European immigrant workers in Oleg; and Kleber Mendonça Filho and Juliano Dornelles, whose Bacurau lambasts Brazil’s venal politics through a high concept sci-fi story. In some respects these imaginative approaches show up the bluntness of the Loachian kitchen-sink.

Loach’s new film follows in the tried and tested mould of I, Daniel Blake – the anti-austerity drama that earned him the top Cannes prize in 2016. Its focus is a driver in a delivery centre run by ruthless employers in hock to the drive for profit. The protagonist, Ricky, is repeatedly sanctioned by abusive bosses for failing to conform to the demands of an automated gadget that tracks his daily routine and reports on his successful delivery rates.

‘Ken Loach’s Sorry We Missed You centres on a driver in a delivery centre run by ruthless employers in hock to the drive for profit.’ Photograph: PR

The film couldn’t be any more overt in its depiction of normal practices and human consideration being consistently overruled by a culture in thrall to profits: in the gig economy, this means cash-strapped workers like Ricky must miss sick days, holidays and family time to meet the demands placed on them. The problem in cinematic terms is that once more Loach’s film misses a further human element: this is a broadside against a culture that sees Ricky as only a cog, but the movie in turn perceives him almost only through his job and a few other lightly sketched circumstances.

The method’s bare bones are there to see. The first act, in particular, sets up a number of bitterly ironic and unjust plot points, set off with varying degrees of believability in the final act. Throw in a stirring tirade, and you have a film that struggles to override its formula. This is a pity because the rightness of Loach’s cause is undeniable – but the methodology is perhaps wearing thin.

Contrast this with the visions of Diop’s Atlantique, winner of the Grand Prix, considered the runner-up prize, in Cannes’ awards ceremony on Sunday. It’s a woozy and sensuous depiction of modern-day Senegal, where exploited workers building a deluxe hotel that towers over an impoverished bay are denied months’ worth of pay, prompting them to attempt to flee to Europe. Diop weaves these elements into a rich, supernatural love story, in which Souleiman, one of the workers, returns as a sort of zombie, white-eyed and feverish, skulking in the shadows, to visit his lover, Ada, and to haunt his venal employer.

Diop’s achievement here is twofold: first, this conceit allows her to present people cast aside by voracious capitalism; second, she shows with real clarity how the rest of the world only sees these people once they have finally become martyrs to their own precarity.

‘Mati Diop weaves a tale of exploited workers into a rich, supernatural love story in Atlantique.’ Photograph: Sebastien Berda/AFP/Getty Images

Rather than present a single-issue film, the director paints a fully realised community, of arranged marriages and virginity tests, of mobile phones and “western” decor used as signifiers of symbol status. Setting the plight of workers abused by big money in this world gives Atlantique’s explicitly political dimension added welly.

Oleg is a Latvian oddity about a butcher who finds himself caught in the clutches of an abusive small-time boss while working in Belgium. The film shows very well how Oleg might have come to end up here, essentially stateless, an umpteenth migrant worker in an “unskilled” sector, making a pittance in a meat factory. Surprisingly, the film operates as a sort of bleak comedy of manners riffing on life in modern Europe, from a dog who has been christened Brexit, to workers depicted drinking together, making up community rituals and playing Fifa on PlayStation.

The film takes on an extraordinary new dimension as Oleg is shown in a quasi-mystical mode, embodying something sacrificial. He is explicitly compared to Jesus, particularly in a beautiful sequence in which he contemplates the altarpiece of a Ghent cathedral depicting the Lamb of God. This process, in addition to a haunting religious score, allows the film to transcend the particular of its story alone.

The tussle between outright “issue-led” realism and an “unrealism” that heightens the film-maker’s concerns, can be seen in the differing methods of Blow It to Bits and Bacurau. The two films belong to vastly different genres: the former, a French documentary, is patient, rigorous and somewhat flat – it pales in comparison to the hot brashness of Bacurau, which was a joint winner of the festival’s third-place jury prize. This isn’t to say that ultra-realism has no worth: scenes in which the auto workers commandeer roundabouts, prefiguring the ongoing gilets jaunes protests, are stirring. But the lack of a metaphorical or overtly visual dimension makes for frustrating viewing.

Bacurau, meanwhile, imagines a Brazillian rural town in the near future, a close-knit utopian community enjoying free love and psychotropic drugs. The film’s directors imagine that Bacurau has been sold out by a corrupt local politician as bloodsport for contract killers, in order to wipe it off the map.

Not everything is successful in Bacurau – far from it. But there’s chutzpah in its amalgamation of political war-cry, folk fable, and western film tropes. The film sides with the small guy, of course – this is standard; but its chillingly believable dystopia is where it gains force. The film is in the business of legend-building, creating a sort of demented iconography of resilience in the face of exploitation.

The plainness of the social-realist mode – an unwillingness to aestheticise suffering and a core belief that simple presentation makes for a more compelling polemic – remains laudable, and Loach has moved filmgoers again with the starkness of his means. But in Cannes this year there was also a different approach, one perhaps more attuned to the ambiguities and compromises of the modern globalised world that reframes social struggle in striking cinematic ways.

• Caspar Salmon is a film writer based in London