The condition isn't the problem, it's the barrier. Many barriers are shared between people with different conditions, situations and environments, so design to overcome the barrier.

If you learn about my conditions, one is dyslexia, you can focus on font design, but proper research has shown that my requirements for a font and those of someone with a vision impairment are almost aidenticle. So if you design for the requirements you will create a font hat is more peformant for people with either dyslexia or vision impairment.

My dyslexia is not the issue but the barriers I can experience when my preferences are not considered by designers is what counts.