Hollywood’s portrayal of astronaut Neil Armstrong in the biopic “First Man” was quick to elicit the attention on Friday of aviation legend Gen. Chuck Yeager.

Social media platforms lit up before the weekend as news spread that Ryan Gosling’s latest film does not include the American flag being planted on the moon. Critics fretted that “First Man” would essentially turn Mr. Armstrong into a progressive caricature when Mr. Yeager, 95, weighed in.

“Ryan Gosling is coming out with the movie First Man where it portrays Neil Armstrong as a liberal progressive anti-Trump (in spirit) non-flag waiver,” a user identified as @ClarenceSwirly wrote. “Probably agree with the National Anthem kneelers, too; at least in Hollywood’s liberal imagination. For your Info.”

“That’s not the Neil Armstrong I knew,” Mr. Yeager — a World War II ace and the first pilot to break the speed of sound — replied.

That’s not the Neil Armstrong I knew — Chuck Yeager (@GenChuckYeager) August 31, 2018

He told another user that the omission of the U.S. flag being planted on the moon constituted “more Hollywood make-believe.”

Mr. Gosling, however, told reporters that “First Man” seeks to show the moon landing as a “human achievement instead of something distinctly American.

“I also think Neil was extremely humble, as were many of these astronauts, and time and time again he deferred the focus from himself to the 400,000 people who made the mission possible,” Mr. Gosling said from the Venice Film Festival, the U.K. Telegraph reported Wednesday. “He was reminding everyone that he was just the tip of the iceberg — and that’s not just to be humble, that’s also true. So I don’t think that Neil viewed himself as an American hero. From my interviews with his family and people that knew him, it was quite the opposite.”

“First Man” is directed by Damien Chazelle and will debut Oct. 12.