Starting with iOS 26.4 and the iOS 26.4 SDK, the .pauses audiovisual background playback policy is not correctly applied anymore to an AVPlayer having an attached video layer displayed on screen. This means that, when backgrounding a video-playing app (without Picture in Picture support) or locking the device, playback is not paused automatically by the system anymore.
This issue affects the Apple TV application as well.
We have filed FB22488151 with more information.