Live and let live. You're the only one teaching people that racial differences are a bad thing. By propagating this negative rhetoric regarding "cultural appropriation" as a negative thing, you are propagating divisiveness, resentment, and confusion.  
As for the comment about the child learning about the realities of disability, and hoping that she becomes a force for change? Change what? You can't erase disability, we have accessibility laws, discrimination laws, and culturally we have a very empathetic society regarding people with disadvantages.  Force to change what exactly?