As noted by 9to5Mac, as reported by users on the Apple Support forums and also on Reddit, iMovie and Final Cut Pro can no longer open Cinematic videos recorded with an iPhone running iOS 16.
The article says the reason behind the bug is unclear, but reports are consistent in pointing out that these apps show an error when users try to edit a Cinematic video. 9to5Mac points out that Apple hasn’t acknowledged bug, and there’s no software update available to fix it. A workaround suggested by some users is to edit Cinematic videos on the iPhone and only then share these videos to the Mac over AirDrop. Since macOS Ventura will be released to the public in October, Apple will probably wait until then to update its Mac apps.