The filled is film with jokes about slavery, and Blacks. The film begs the audience to laugh at slave ignorance and c00nery. It also wants us to laugh at how ridiculous those pale faces with hoods are...Asking us to find humor in a group that would go on to massacre, rape, oppress Blacks for the next 120 years.
A good 2/3 of the film is spent explaining why slaves are inferior to whites or are best compared to animals; even Django adopts this mentality under the German's request. I'm sure QT went through all the possible plot scenarios and found the mythical "mandingo fights" to suit his story the best but why not include some counter anti-slavery dialogue. I guess not even the slaves back then thought negroes were worth a damn in the head.
In reality, white racists believed Black men were violent creatures that needed to be controlled. If said negro wasn't controlled or was freed, White families were in danger, particularly white women. No only does Django fulfill our modern angry Black man archetype to a T (understandably), he goes on a killing spree. Once Django obtains his "reward", he continues this killing spree and even takes out an innocent white woman, the pale face on that farm who was nice to his girl.
QT tried to sell Django as a Black hero
The German was more disturbed by slavery than Django. Yeah yeah Django was used to it but that doesnt mean it shouldn't bother him. Django was more concerned with his wife than the slaves he went out his way to shyt on slaves to appease Candy. If QT wanted to make a Black hero, Django would've at least empathize with the other slaves. He would've made Django inadvertently spark a slave revolt, throwing everything Candy said about slaves back in his face. Django would've gained his own freedom and he would've killed Candy. Instead we have a White man freeing Django and destroying the man who is the sole cause of Django's pain. The White man giveth and taketh.
And I could go on