The fundamental problem is cases like this lawsuit is that there are people who genuinely believe that their kind of life is the kind of life worth having and that lives which are not like theirs are at the very least quite significantly less worthwhile, so much so that we should end those lives as quickly as possible.
This is of course the same mentality advanced by eugenics advocates, though with an emphasis on how warm and fuzzy a position it is and how compassionate their goals are. Their eugenics is the friendly eugenics done for your own good. They really do have good intentions in many cases, which makes their actions all the more terrifying because there is no way to stop it. No policy, no guilt, no shame is strong enough to keep them from doing what they honestly believe is the most compassionate thing. They are content to have you killed because their moral intuitions tell them that a life full of suffering is not worth living in complete disregard for the fact that all of our lives are full of suffering (even the most physically comfortable ones) and that the logical consequence of their belief is that we should all be killed.