The Web is great for accessibility in the traditional sense of the word. Information is accessible. The HCI sense of accessibility is completely dependent on the Web page authors. The hoards and hoards of them, who are using a technology that was specifically designed to be used by people with no training in the medium.
Unfortunately when differently-abled people are simply another user segment there is absolutely no way to get business resoures to address them because they sadly aren't your target market. That's been my experience amyway. IMO it's one of the biggest issues with agile: MVPs aren't accessible (among many other things).
