@Reaperoa, you’ve inspired me to try my hand at Choice of Wild West Writing.
*choice
#1.1 Make everyone get along easily, except maybe a few over-the-top racist villains.
Congratulations! You've made America's genocidal westward expansion seem like a broadly heroic enterprise, only marred by a few bad apples.
#1.2 Be honest to the real-world racism, exploitation, and mass murder.
OK, Gritty McNasty, but will you...
*choice
#2.1 Have the racism etc. just be background color to add some realism. You aren't writing "about" it, you don't want to comment on it, you just want to be true to the period.
Cool. Your otherwise sympathetic protagonists are authentic to their time, and treat American Indians, blacks, and Chinese people as less than human. (Because obviously, if you've picked this choice, you're writing about the cowboys). And... well, that's it. Guess it's not worth trying to flesh out those other characters at all, or suggest that they're more than their stereotypes. They're just here to add, er, color.
#2.2 Try to write a story that comments on it at least a little.
All righty, Sheriff P.C. Wellmeaning, which brings us to...
*choice
#3.1 Racism kills people and ruins lives. My story is going to show how bad racists are. Most people will be racists, and every racist will be a villain. The racists lose, the oppressed win. Yay!
See, you've got this hammer. This big, impossible-to-miss hammer of righteousness. And I agree with you, but... your story is hitting it repeatedly against my head.
#3.2 I'm going to write a story set in a time of racism, exploitation, and mass murder... and whether or not that's what the story is <i>about</i>, I'll convey through the characters and their relationships both how it's possible for privileged people to buy into all that shit, <i>and</i> how oppressed groups respond to it, resist it, and have lives apart from it... and I'll write in a way that maintains their dignity, and everyone's humanity.
Good luck, Long-in-the-Wind