@thatguyoverthere Well, by your analogy, let's imagine some person doesn't have a hand. Can he be a productive member of society — sure can, there are jobs other than working in the field. Can he live a normal life — with proper infrastructure, sure can and our society is developed enough to provide it.
So this person demanding to be taken like a normal member of society is quite okay — and that is what most of them want (no reason to pretend that he has a hand, it's obvious that he doesn't).
@thatguyoverthere Some of it might be treatable, some might be like, following your analogy, pancreatic deficiency — digestion of this person might work mostly like the one of a healthy person, but he might supplement it by taking enzymes, this will improve the quality of life immensely — even if he/her has to take those all his life. He can sometimes live without those, but why?
I don't think that, for example taking antidepressants all your life is necessary, for some maybe it is…
@thatguyoverthere Despite it being actively studied, it's still mostly terra incognita and people often fall for extremes, some might want to MAKE these people behave normal, others might demand taking them as they are — both probably aren't the solution.