You could require that all devices capable of video or audio display or capture embed models to detect copyright-protected content, and only proceed with playback or capture if they are connected to the internet and are able to verify some cryptographic liscense is valid. Put all this logic in some secure processor that self-destructs at the slightest sign of potential reverse-engineering or irregular behavior, along with physical anti-tampering measures that make phreaking or uncapping any components liable to trigger self-destruction. Then make the circumvention of any of these measures or attempts to create or import non-compliant display or capture video or audio content carry some heavy criminal penalty, such that any group well-resourced enough to attempt bypass would judge doing so foolish.
I genuinely can't imagine any other form of DRM being successful.