At Slate, Jan Swafford, who knows a bit about the subject, on biopics about musicians and balancing the truth with entertainment in a movie like 'Coco and Igor':
Leading man Mads Mikkelsen has studied photos of Stravinsky in that period and he nails the look. In those days Stravinsky had an unhandsome but chiseled, fiercely self-contained face. He didn't look like the Romantic idea of a composer; he looked like a Brancusi. In the movie Stravinsky plays a period Steinway, and his playing has a curt, percussive quality that is exactly right. (Mikkelsen is probably faking the playing, but it's actually hard to tell.) The movie implies Stravinsky's heavy drinking started with Chanel's rejection. Although, as a Russian artist, he was probably devoted to the sauce all along and drank as if every night were the eve of Prohibition, I'd call that acceptable dramatic license.
On Stravinsky's assessment of his ability to compose:
"It's as if I open a door and the music is there." Stravinsky was virtually in awe of his own gift. He didn't know where it came from. Neither did Mozart. Both made the default guess, which was God. I don't know whether Stravinsky said that line about the door, but he did say this: "I am the vessel through which Le sacre du printemps passed." And, as in the movie, he probably kept a cross on his desk.