Re: Everything should be as accessible as possible.
This is a poor argument. You have said that your ereader assists you by allowing larger text - it is, therefore, doing what it is designed to do. What more do you want? If you want something that does text-to-speech, then an ereader is not the correct tool - you need something else. In essence, a text-to-speech device for the visually impaired would be wholly different from an ereader - no screen, for instance.
You seem to arguing that every ereader should have a speaker and software that most people will never use, at the expense of the people that will never use it. This is wrong. There is absolutely no reason that a simple device should be encumbered with stuff that the majority will never use merely because it makes the life of a small minority easier, and when reasonably-priced alternatives exist. What next - every phone has to come with giant buttons so that people with visual impairment or lack of mobility in their fingers can buy the same as everyone else?
There is a huge difference between ensuring that ramps are available for people with mobility problems, and special surfaces exist for visually impaired to help them identify crossings etc (though they cause problems for people with mobility problems). It is something entirely different to demand that the manufacturers of goods to to fit the needs of all disabled people.
Out of interest, have you read Harlan Ellison's "Harrison Bergeron"?