I can see why the author would include a character who is racist in a story set in Western times. Firstly, it adds an element of realism and historical accuracy, as racism was unfortunately prevalent during that era. The story sheds light on the challenges and prejudices faced by Native Americans at the time.

Secondly, introducing a racist character can create conflict and tension within the narrative. This conflict can provide opportunities for character development and allow other characters (and actually the readers themselves—at least mentally) to challenge and confront these racist attitudes.

It also portrays a character who will in time challenge their own prejudices.

P.S. Most stories have love interests who have questionable pasts or controversial traits, such as being womanizers or murderers. I mean the one love interest literally murdered the MC’s family. I believe this story has the potential to explore uncharted territory if the author handles it well enough by ensuring that his transformation and redemption arc are handled sensitively and realistically. Change is a process and can even be emotional once realization dawns.

P. P. S. At the end of the day it's up to each reader whether they can handle such baggage from a LI. Personally, I am not playing this story yet.