Every time a new movie about a gay relationship comes out, the question gets asked: “Why did they have to cast straight actors?” White actors playing characters of colour is seen as inappropriate; what about straight actors playing gay characters?

The issue has risen again with Call Me By Your Name, a new film detailing a romance between a precocious teenager (Timothée Chalamet) and the Adonis-like American grad student (Armie Hammer) who’s staying at his Italian country home. It’s already being talked of in Oscar terms. Does it matter that both leads are straight? As were Jake Gyllenhaal and Heath Ledger in Brokeback Mountain; Annette Bening and Julianne Moore in The Kids Are All Right; Jim Carrey and Ewan McGregor in I Love You Phillip Morris; and so on.

The film’s director, Luca Guadagnino, has a valid response: “This film is about the blossoming of love and desire, no matter where it comes from and toward what. So I couldn’t have ever thought of casting with any sort of gender agenda … I prefer much more never to label my performers in any way.”

Straight times ... watch the trailer for Call Me By Your Name.

If only others in “liberal” Hollywood thought the same. A 2013 survey found more than half of LGBT performers had overheard homophobic comments on set, and felt that studios found it harder to market LGBT performers.

Actors back this up. Thorn Birds heartthrob Richard Chamberlain, who came out in 2003, later said he “wouldn’t advise a gay leading man-type actor to come out”. Rupert Everett said he didn’t work in Hollywood for a decade after coming out, and last year Ellen Page complained that she was suddenly only being offered gay roles. “Now I’m gay, I can’t play a straight person?” she asked.

It was a rhetorical question but, in 2010, Newsweek writer Ramin Setoodeh suggested exactly that. Reviewing a play starring Will & Grace’s Sean Hayes, Setoodeh wrote: “It’s weird seeing Hayes play straight. He comes off as wooden and insincere, like he’s trying to hide something, which of course he is.”

If you are openly gay, your sexuality trumps your talent and your career could suffer. Straight actors playing gay, though, are brave, deserving of Oscars. It has worked for Tom Hanks, Philip Seymour Hoffman, Hilary Swank, Sean Penn and Jared Leto. Meanwhile, no openly gay or lesbian actor has won. Despite Guadagnino’s fine sentiments, if Call Me By Your Name figures in this season’s awards, it won’t change that. Is it time for an #OscarsSoStraight moment?

Call Me By Your Name is in cinemas on 27 October