Nobody said that. They are saying or insinuating that 38% of successful students are unlikely to be disabled. That certainly was not the case as recently as a decade or two ago. People have not changed drastically, so what gives?
Which is an unreasonable claim.
I have a disability that impairs many aspects of my life. I was still capable of getting through college and am successful in my career. Having a disability does not mean you can't do academics.