Can you explain in more detail? As a person ignorant of these types of issues, I'm having a hard time understanding the connection between the lack of accessibility in an app to the firing of a blind employee.
Here's what happened as I remember it. The blind employee, Darrell, was providing technical support for a client company on behalf of his employer. At some point after he had taken on this role, the client added a requirement that anyone who worked with them had to use the Seibel CRM system in "high interactivity" mode. If I recall correctly from talking to Darrell, the high interactivity version of Seibel at this time (2006) used the Microsoft JVM. That, combined with the fact that the app implemented some custom controls with no regard for accessibility, made it completely unusable to him. So his employer laid him off. Luckily for him, they rehired him shortly after that, but only because they found a whole new role for him. One can question whether the real problem was the app developer, the client, or the employer. But the inaccessibility of the app was a critical factor.
If this application is important to people in general, it wouldn't stop being important just because you happen to be blind or otherwise disabled. If everyone uses a particular walled-garden service for some daily task, blind people need to use it too, just the same as everyone else.
I was talking about app developers that build applications for jobs that require sight because of the nature of the job. Say a medical diagnostic application or airplane (simulator). You have to develop for the color blind, but for the completely blind, not so much. When selecting an UI toolkit I do not have to put that requirement up top.
For all the others, I wonder if a command line interface wouldn't just be better—sometimes not just for the blind.
I’m the last to say blind people are an afterthought which is why I thanked the original commenter for his reminder. I merely want to bring some nuance that there are always exceptions.
But we have to deal with reality here. Some tasks simply require normal sight. Believe me, as a legally blind person myself, I wish I could drive, but I understand why I can't and accept it. The same applies for some software applications. So all I can ask is that developers pay attention to accessibility unless there's some reason why it just won't work for their application. I think that's what your interlocutor is getting at as well.
In my ideal world, all user interfaces would run on the user's main portable computer (currently a smartphone), controlling devices remotely over Bluetooth, NFC, or the like. Embedded UIs would then be a thing of the past, and accessibility would simply be a matter of following the recommended practices for mainstream general-purpose platforms.
Again, thanks for reminding everybody. People need to think about it. Your advice could be toned down a bit to “please think about your audience, if you expect people with disabilities to be part of it think twice when making your own UI toolkit, or at least factor in the costs to build in accessibility features.”