What absolute bullshit. "the danger that programmers will be jailed". How?? What will programmers be jailed for?? Oh right, there's nothing in this proposal that makes any kind of programming illegal.
Literally all this is is a specific plugin API for protected media content. It's literally no worse than the current situation of using the proprietary Flash plugin through the browser's general plugin API.
Now, while I don't personally see how it's any better either Tim Berners-Lee does think this will make it easier to have more portable protected video content. It's either that or we continue to use proprietary DRM plugins anyway.