Boozer, this issue is not as clearcut as you make it seem. The survey you cite is old and has some issues. https://ipclinic.org/2014/02/11/11-reasons-to-ignore-the-10-year-old-annenberg-survey-about-the-washington-football-teams-offensive-name/

For example do you think 90% of Native Americans feel that Chief Wahoo is a tribute to their collective cultures? In addition the National Congress of American Indians has taken a very strong stand against the use of derogatory Native American imagery.   
http://www.ncai.org/proudtobe

I'm a huge proponent of elevating the complex history of Native Americans. We might start by acknowledging the massacres of natives by Oregon settlers in the 1850s. http://bluebook.state.or.us/cultural/history/history14.htm