From what I've seen in the other thread, most people complaining about "reverse discrimination" felt that one should get a job only based on their ability to do the job, regardless of gender or antyhing else.

It follows that if a person with a disability can't do the job then they shouldn't be hired over someone who can, but doesn't have the disability, in the same way that one who can't do the job but is female should not be hired over someone who can but isn't.