Having no legs at all could make you stronger because <insert many reasons>, but nobody cuts their legs off because, objectively, it can cause a lot of problems in your life.
With how many people feign illnesses and problems like badges of honor, I don't even know anymore. It might just be a matter of time.
Otherwise people tend to on a deep level fear self mutilation. Even with good reasons to do it they will struggle to cut off their legs even when their life depends on it, which makes it difficult to not justify excuses for keeping them.
Of course I want my legs, I value my legs, but there's got to be some weirdo out there that doesn't want legs who might actually become stronger as a person through losing them, or some guy who through losing them finds a strength that was otherwise once dormant, like discovering a talent for Wheelchair Rugby that sets him for life.I understand your viewpoint, Turncoat, and I am sure you understand mine.
I do get yours, it's a pretty straight forward and typical argument: "You should aim to grow, function, and succeed". I'm not sure if you'd expand that to benefiting larger groups of people or if you're focusing more on a sense of personal progress, but you argue for a sense of growth that can be argued to "exist" beyond a sense of the self (objective), so in ways that could be compared to others from it's basis in "reality".
I do not think Daniel Birdick's point is that his world view is superior to yours. I think he makes a clear and valid point when he more or less says that cutting your legs off to make yourself happy has the same practical issue as buying a lottery ticket to become a millionaire. I agree with him. Claiming that everything is relative is not very practical. It just gives a good excuse not to do anything to address real life problems..