When technology breaks down the barriers

Here's a good example of how technology can aid unlucky people to integrate themselves in the digital world and more, because the fields of applications are more.
IBM presents the avatar that communicate with gesture for non-hearing people.
Very good!
But we can think to all the enormous material audio/video available in the net (in particular way on YouTube and at the videos shared with peer-to-peer) that is not accessible to non-hearing people.
Why we don't begin to think to this people that have our same rights and, all things considered, also them are cnsumers? I don't believe that they are just a niche and if we consider all people with a powerless sense of hearing, like ancient people, is possible to count million of people!!