For most of his four-plus decades in Hollywood, Thomas R. Moore has worked as a picture editor on network television shows.

During a typical year, his work followed a pattern: He would spend about a week and a half distilling hours of footage into the first cut of an episode, then two to three weeks incorporating feedback from the director, producers and the network. When the episode was done, he would receive another episode’s worth of footage, and so on, until he and two other editors worked through the TV season.

This model, which typically pays picture editors $125,000 to $200,000 a year, has mostly survived the shorter seasons of the streaming era, because editors can work on more than one show in a year. But with the advent of artificial intelligence, Mr. Moore fears that the job will soon be hollowed out.

“If A.I. could put together a credible version of the show for a first cut, it could eliminate one-third of our workdays,” he said, citing technology like the video-making software Sora as evidence that the shift is imminent. “We’ll become electronic gig workers.”

Mr. Moore is not alone. In a dozen interviews with editors and other Hollywood craftspeople, almost all worried that A.I. had either begun displacing them or could soon do so.

As it happens, these workers belong to a labor union, the International Alliance of Theatrical Stage Employees (IATSE), which can negotiate A.I. protections on their behalf, as actors’ and writers’ unions did during last year’s strikes. Yet their union recently approved a contract, by a large margin, that clears the way for studios to require employees to use the technology, just as Mr. Moore and his colleagues have feared.