I had the fortune of working for a very small company that made electronic vision enhancers and portable readers for visually impaired people. We were just 2 developers and there were about 15 people in total mostly doing electronics, assembly and marketing.
It was very surprising how dumb our intuitions can be about what's important for our customers and what isn't. And how easy it is in daily grind to make something that can't actually be used by a blind or elderly person. I think they would be better of if they hired at least one blind developer, even if (s)he worked a little slower.