Revisiting films on the occasion of major anniversaries can be a disorienting reminder of time’s too-swift passage: that film is now 20/30/40 years old? How can that be? Why does it still feel so much younger than I do? In other cases, however, the film wears its advanced age in a way that makes complete sense, and so it is with Last Tango in Paris, released in cinemas in 1973. Now a half-century old, Bernardo Bertolucci’s lightning rod for scandal and debate has dated in many of the ways you might expect, but that’s not quite what I mean: at 50, the film’s age has now caught up with the overriding air of middle-aged despair and disarray that it always carried. In a sense, it was a film made to be forgotten, and then remembered with bittersweet, conflicted feelings, its significant beauty curdled over time.

Bring up Last Tango in Paris in cinephile circles today – especially those reckoning with the gender politics of the artform post-MeToo – and you won’t hear that many fond endorsements. When it’s brought up at all, the conversation swiftly narrows to its most notorious scene: the one where Marlon Brando’s Paul, a recently widowed American abroad, holed up in a desolately furnished Parisian apartment, forces himself on Maria Schneider’s Jeanne, a 20-year-old ingenue whose name he refuses to learn. Grabbing a dab of fridge-cold butter for lubrication, he anally rapes her.

The sex is simulated, but as recalled by Schneider on multiple occasions before her death in 2011, the scene felt like a violation anyway: one she claimed was sprung on her without due notice or preparation by her older male director and co-star. “I felt a little raped, both by Marlon and Bertolucci,” she said in 2007; watching the scene today, it’s hard to observe her vivid, sobbing onscreen distress and not feel queasy about the means by which it was extracted. Ten years ago, Bertolucci responded to the allegations by insisting that the scene was not improvised on the day of shooting, though Brando’s now-notorious reach for the butter was: “I feel guilty, but I don’t regret it,” he said.

Not much of a mea culpa, then – not that one was ever to be expected from this most brazen of auteurs, an artist often disinclined to let good taste and decorum interfere with his pursuit of sensualism. But Last Tango in Paris operates in a mode of intense, intentional discomfort. It doesn’t excuse or disguise the repeated abuse and exploitation of Jeanne by other men as anything more romantic or consensual than it is, though this briskly amoral film doesn’t condemn such degradation either. Bertolucci depicts how people wound others, or submit to such wounding, with the kind of aloof male gaze that can afford such relative disinterest. It’s certainly not a film that instructs you how to feel its characters, violator or victim; it takes our potential disgust in its stride.

Yet what newer generations of detractors may overlook is that arguments over the merits of Last Tango’s portrait of patriarchal exploitation – versus its own patriarchally exploitative methods – are as old as the film itself. Last Tango in Paris opened to a storm of seething outrage from multiple, disparate sources: it was the rare film that could unite conservative moral guardians and second-wave feminists against a common target. As censors baulked over its explicit sexual content and frank sodomy scene (and Mary Whitehouse protested that its X rating from the BBFC wasn’t restrictive enough) more progressive critics lambasted the film for the alleged superficiality of Jeanne’s frequently compliant, masochistic character, and its framing of her mostly through men’s eyes – not just Brando’s anonymous, decades-older lothario, but her callow, opportunistic film-maker fiance Thomas (Jean-Pierre Léaud) who, with a camera crew constantly in tow, insists on making Jeanne the star of an off-the-cuff docufiction she’d rather not participate in.

Is Last Tango in Paris sufficiently self-aware and metatextual to present Thomas as an analogue for Bertolucci himself, wielding a prying lens to capture his leading lady at any cost to her sanity? Perhaps, though Bertolucci, only in is his early 30s at the time, admitted to seeing Paul, by turn a detached observer and a violently fascinated aggressor, as his alter ego within the film – using that identification as his rationale for protecting both Brando and his character in areas where Schneider and Jeanne are most literally exposed.

Brando never appears nude on screen, gesturing instead to his softened middle-aged physique through layers of knitwear and some awfully chic coats. All the while, Vittorio Storaro’s camera – its every exquisite composition luxuriating in a veritable paintbox of flesh tones — grazes over Schneider’s youthful breasts and au naturel pubic hair. “To show him naked would have been like showing me naked,” Bertolucci later admitted. Egregious double standard or a film-maker’s candid, self-implicating admission of masculine vanity and insecurity? Once again, Last Tango in Paris doesn’t much care what you think.

The demographic line between the film’s advocates and opponents has never been an altogether tidy one. In the critical sphere, some of its key defenders were women. Following a fractious premiere at the New York film festival, it was a typically fiery review from Pauline Kael that argued for, and perhaps booked, the film’s place in the canon. “Realism with the terror of actual experience still alive on the screen – that’s what Bertolucci and Brando achieve,” she wrote, somewhat perversely excluding the palpably terrorised Schneider from that claim, even as she declared Jeanne the victor in the film’s erotic gender war. “[She] must be the winner: it is the soft ones who defeat men and walk away, consciencelessly.”

Kael’s was not a perspective that begged for agreement: indeed, she offered a prediction that Bertolucci’s film would be debated “for as long as there are movies”. You don’t even need a fellow viewer to get an argument under way: today still, Last Tango in Paris offers enough lyrical beauty and repulsive cruelty, often held in the same shot, that I still can’t tidily say how I feel about it. Many viewers may be unmoved by the openly pathetic vulnerability of Brando’s tremendous performance, crescendoing in an agonised monologue beside the body of a wife who recently killed herself, but it’s some of the most dangerous, unguarded work of his career – attached to a character who can invite our hatred one breath later. Rarely has a film, in both its constructed fiction and its very being, captured the arrogant, destructive impossibility of men to quite such bruising effect. Do we need it, though? No more or less than we ever did.