That is completely psychotic blacking out single frame screenshots for copyright reasons. Copyright is truly out of control and just comically ridiculous at this point.
It's not blacking out on purpose, rather it's a side-effect of the DRM chain. The DRM content is rendered outside of the UI chain, so it cannot be captured as part of a normal screenshot or video. The same happens on macOS (and even windows) if you try to screen record while watching DRM L1 content such as Netflix, Apple TV+, etc.