This is the most wtf thing I have heard all day. Basically "me can't have so you can't have." It's like shutting down a public Library just because it doesn't have a ramp for people with wheelchair. Do people really go hmm 10 out of 100 people cannot have it so the other 90 will not have it too. Doesn't make sense.
I don't understand anyway since screenreaders are a thing on computers and smartphones and you can load an ebook into either. Meanwhile a paper book either needs a very expensive braille copy or some kind of complicated electronic shit to read the book for you.
My guess is the publishers knew ebook piracy is a thing and bribed some officials to use the ADA line.