People are not cars, and most of the time "fix" is problematic as people don't need "fixing" - spaces do. The solution to someone unable to walk is not to fix their legs (which, for most, e.g. amputees, spinal injuries, birth complications is impossible), but to build a ramp instead of a staircase. Unless you happen to have, on hand, a way to "fix" Downs Syndrome, Autism, Dyslexia?

People who can't use a staircase aren't "special," as both you and I and everyone else will inevitably either reach an age where we can't use a staircase, or will happen to die before that happens - but either way would be been inevitable. Unless you happen to have, on hand, a way to prevent the aging process?

EDIT: also, if we're getting super pedantic about word definition, if it has to be truly "unique" - ie a set of exactly 1 - then either everyone is unique or no one is, and therefore the usage of the term is equally moot for a different reason

edit: again, are you absolutely sure the objection is because "complex needs" is truly impossible to understand, or actually because changing a learned behavior is sometimes uncomfortable and requires effort?