Its not like the movie is going to be him saying the equivalent of "nigger" towards native anericans.
Except it pretty-much IS. And then some.
"Ridiculous Six" is white folks making mockery of Native folks... and that's it. No mutuality, no "everyone's in on the joke" - heck, they asked politely for script changes, to tone stuff back a bit, and instead they were ignored and the script was made worse. Repeatedly.
One of his main jokes is having a Native woman be named "Beaver Breath". She at one point squats naked in the middle of a scene and pisses while casually smoking a shamanic peace-pipe (basically defiling a sacred religious symbol, then is later talking with an older one named "Never Wears Bra" about wiping her ass with a dead squirrel after shitting (disrespecting the tribe's views of cleanliness and respect towards women), and another scene involved the feathers comprising another sacred symbol getting rearranged to make a sexually-vulgar shape (more defiling of religious icons).
They hired a man from the Apache tribe to act as a cultural advisor, to make sure that nothing they said or showed was too disrespectful in how it portrayed the Native People... and then proceeded to completely ignore every single complaint and request that he and the rest of the Native cast gave them. Then they told the Native cast, basically "if you don't like it, leave." So they did.
Hell, this movie already had the potential to kill someone, due to the set's terrible safety standards. One of the extras had to aim a 60lb-draw longbow with real steel-tipped arrows at one of the Native American actors. This extra also had no training in handling such a weapon and if it had gone off it would've killed someone.
I mean, they hire a cultural advisor yet take none of his advice, the Native actors were expected to just sit back and keep quiet as they see their people's way of life, naming traditions, traditional styles of dress and grooming, social customs, and even sacred religious symbols all being disgraced and desecrated... and even put them in scenarios that literally are one minor slip from being fatal... yet the producers act surprised when the non-white people get pissed off and leave after they basically have every aspect of their existence as a people dragged through the mud for the sake of white folks making crude and vulgar jokes at their expense.
This movie is Sandler giving the Native People all one huge middle finger and screaming FUCK THE INJUNS! for no apparent reason beyond he personally thinks it's funny.