Explain why it needs changed and what is offensive about it. Not everything has to change just because things change
That's an easy one. It needs to change because a very small percentage of people find it offensive, or at least they say they do (as a means of exerting power just to exert power).
A few years ago Sport Illustrated, along with the Pew Research Center, did a poll of Native Americans, and found that a full 83% found none (as in not even one) of the high school, college or pro sports teams' names or logos offensive, Something like 12% found one or more offensive, but it was only about 2 percent that found any and all Native American names or mascots offensive.
There certainly have been some whoppers, like the Wahpeton (North Dakota) Wops, the Pekin Chinks, the Coachella Valley Arabs, Freeburg Midgets, East Akron Orientals.
My favorite is the Fighting Nads of the Rhode Island School of Design...