I think you're completely missing the point.
It's a different situation because even though the word "hoosier" originated as a race-based derogatory term, Indiana natives have turned it into a positive term with which they readily identify.
However, if some Indianans deciced that they were now offended by the University of Indiana calling its athletic teams the "Hoosiers" because of the term's derogatory origin, shouldn't they have just as much right to demand that the university change its name? Would the NCAA back them?
Let me put it another way. I once had a Native American tell me that he opposed UND's nickname because, "They're not Sioux. They're a bunch of white boys playing hockey."
If someone said, "They're not Hoosiers. They're a bunch of black boys playing basketball," that person would rightly be labeled a racist.
The situation is different only because the targets of the original "hoosier" snub chose not to take it that way, chose not to make it race specific (even though it was) and chose not to claim sole ownership based on race.