By default, a file with HEVC video codec is created with "hev1" as a video codec ID. And on MacOS (QuickTime player or Final Cut Pro software) the file is not recognized as a proper HEVC video.
With a default encoding configuration:
format='mp4' video::codec='n265' audio::codec='aac'
You get a file with the following information:
By specifying a video tag in encoding configuration to "hvc1" so the configuration looks like:
format='mp4' video::codec='n265' audio::codec='aac' video::tag='hvc1'
The resulting file has a different Codec ID:
And the resulting file works fine for MacOS.