Apple has just released TVOS 11.2 for the fourth-gen Apple TV and Apple TV 4K, as noted by 9to5Mac.
The update fixes one of the biggest issues with Apple TV 4K by adding content-matching options for video. Specifically, the Apple TV 4K can now be set to match Dynamic Range, which will not be forced to upscaling content to HDR; instead of "play content in its original dynamic range". and Match Frame Rate, which will "play film and international content at its original frame rate."
