I strongly agree with you in general. However, can you provide a pointer to more information about the accessibility problem? One might argue that integrating DRM with HTML5 media playback would actually improve accessibility, since it would separate the DRM from the generally inaccessible Flash-based UIs of current players.
There is no difference between the proposal and existing closed-source, proprietary blobs like Flash.
All the W3C is talking about here is standardising the interface between Javascript and those blobs. There is no way in which the presence of EME support in a browser will improve accessibility.
Consider an example. Before EME, content is rendered in an accessibility-invisible Flash plugin. After EME, the exact same thing is true, only there is now a standard way for the browser to control the plugin.
