Open source and DRM are fundamentally incompatible—if neutering the DRM is a mere recompile away, what good is it to the sorts of organizations that require DRM?
DRM'd media is encrypted and cannot be "neutered" if you don't have the decryption key. [Well-designed] DRM relies on secret keys, not secret source code.
Here's the problem: either you have the decryption keys and can get to the content, or you don't and can't. If you can watch a movie on your computer, you already have everything you need to pirate the movie.
Which, of course, is true for any cryptography, regardless of the openness of its implementation. It may be harder to keep the keys obscured in open code, but then the keys usually don't stay secret that long anyway.
XOR is the best DRM. Since all DRM is breakable since you need the decryption key to play the content, the purpose should be to trigger the copy-protection-protection stuff in the DMCA, and XOR is the simplest way to do that.
It's actually coming. If you go to about:flags in chrome, there's a flag called "Enable experimental Encrypted Media Extensions on the video elements.".
