Set Top Box proven unnecessary by the Cable Companies

I wanted to comment on the fact that cable companies continue to insist that they need to have set top boxes to control the flow of content and prevent it from being stolen. With the release of live TV for viewing on the Xbox 360 they have clearly shown that the content can be successfully controlled by software, up to even their own ridiculous standards. Why this isn't proof that cable companies should have to provide those API's for competitors to access the content and that no new DRM/content access scheme needs to be developed, I just don't understand.