You are bringing up censorship why exactly Mike? You are the one calling for "pylon" to be censored. Nobody is censoring the use of the word retard.
If someone directly refers to someone as a "retard" for doing something they disapprove of, they directly show disrespect towards that person, but they obviously also indirectly show disrespect for people with Down's Syndrome. There is no disrespect for pylons as far as I can ascertain.
Personally. I had a bit of a problem with Tarantino's use of language. It was correct to be historically accurate, but his film was not all that historically acurate, and the language was used more in a sensationalist manner as a whole. The film was a whole lot of noise without much meaning once it got past the halfway mark. Sadly that's about the acceptable extent to which race can be discussed, even while presenting a narrative about slavery. And that whole situation is completely different from the simple respect being requested for people that can offer a lot to all our lives while they come up against disadvantages that many times society unnecessarily magnifies, including through the use of - yes - words. You complain of having gone through a process of being diminished by the state, and yet dismiss how a culture can diminish people that they feel do not deserve the respect required to be included in that culture.