I think it's not so much the disabled elite themselves, but the way they're portrayed to sweep the realities of disability under the rug. They make "normal people" feel less concerned about the plight of the disabled.
Temple Grandin is an outlier. She makes it look as if this disability is really no big deal and that, given enough hard work, if she can do it, anyone can. Thus, it's not really a disability if the disabled person doesn't allow it to be.
And, of course, Grandin loves the limelight. Though there's a lot of positive and role model stuff, and destigmatization, she alone can't be the bellwether or even the mean for being on the spectrum.