> It shouldn't be done.
That's linguistic prescription. "This word means what it means and if you change it you're incorrect".
I'm not saying that. My position is it shouldn't be done because creating new slurs for no reason is stupid. A prescriptivist and a descriptivist could both agree to that, though they'd disagree with each other on whether the idea of the change is legitimate.
Which is probably a similar position to ccmcarey's original comment. No position was taken on whether the change breaks the rules of language or not, the argument was that either way the change is being bought on by ignorance of both normal usage and the lineage of the word (ie, potentially in defiance of both prescriptivist and descriptivist logic).
This isn't really an issue of prescriptive vs descriptive philosophy. Although the descriptivists will be hopping mad.
It seems like a mistake to invent racial terms out of whole cloth for no reason. It shouldn't be done.