Surely it's easier to argue that we should have no people without legs rather than no people with legs
But that's not the question at hand. Maybe there's a benefit to diversity of perspectives. In which case the question should be is society better for having 1% (or 10% or 0.001%, anything above 0%) of the population disabled?
& there's the "everyone has different disabilities", some extreme would say I shouldn't've been born because I was diagnosed with ADHD. & the slippery slope of racial eugenics
Which all gets to this premise: we shouldn't be trying to create a world with a population of 10 billion clones
Now whether the natural diversity ratio is too high or too low, I'll reserve comment