Apple has announced a new Dolby Atmos feature available to Apple TV with the tvOS 18.5 software update released yesterday.
According to the release notes, this update enables Dolby Atmos playback to be synchronized with external speakers connected via AirPlay or Bluetooth.
What's new in tvOS 18.5 This update adds support for synchronizing Dolby Atmos playback to speakers over AirPlay or Bluetooth. To use, go to Settings > Video and Audio > Wireless Audio Sync.
This is the only new feature Apple has listed for the software update; however, it likely contains general bug fixes and improvement as well.