Spatial audio on Apple TV 4K, which can take a 5.1, 7.1 or Dolby Atmos source and simulate a dynamic and immersive sound field in headphones, is currently limited to one pair of AirPods at a time. Connecting a second pair in tvOS 16 will make audio fall back to traditional stereo.
FlatpanelsHD has discovered that tvOS 17 will finally add the option to share spatial audio between two compatible pairs of AirPods and Beats, meaning that both pair of headphones deliver the spatial audio experience which is much better than what most built-in TV speakers and soundbars deliver.
Shared spatial audio works with content sources in multichannel 5.1 and 7.1 as well as Dolby Atmos in apps that support spatial audio, including the Apple TV app and Netflix.