Let me give you an instance...
I'm working on a novel right now that takes place in 1961. It was the time of a lot of unrest on many different fronts.
Issue one: Vietnam war
Issue two: Civil Rights
Issue three: Religion
Let's review each of my problems. With issue one I want to make sure I put in the correct information about the war. I don't want to glorify nor do I want to skirt it. The war doesn't have a lot of play in my novel but it does play a minor role for a character. The governmental processes change by the minute and what is done today regarding a situation, say death, is handled similarly but also differently than say back in 1961 or even back in 1944 or in 1919. I don't want to set off a flag to anyone who is familiar with protocol of that period.
Issue two involves Civil Rights which was also happening. It was a time with major historical actions and again, to wishy-washy my way through the story would be an insult. But, I also have another problem. In the North, we spoke differently than down in the South. We used terms to describe those of another race. Yes, they were slurs and very derogatory but nonetheless, they were spoken; sometimes in anger, sometimes from a bigot. Back in the 50s it was very common for a white person to slur those of another nationality -- I could list them, but there is no reason to; we all know them to represent those who are Black, Jewish, Italian, Hispanic, etc. For my story I want to be true to the period and the talk. I've used LinkedIn to discuss this with other writers and the general rule seems to be "don't sanitize the ugly" and if somebody gets offended, so be it. Reality is truth.
With issue three I have a couple of religious issues working. One is more a 'way of life' than religious but for the Amish, religion and life are very intertwined with rules. My research into that lifestyle was very enjoyable and enlightening. The Amish people I spoke with were very open and most were willing to discuss their ways. I have those non-Amish (English) characters interacting with Amish characters and vice-versa. Again, I want reality, not some trumped up concoction to make my story more fantasy than reality. Yet, I don't want it to be boring because it will be a piece of fiction based on some truths.
Obviously since the story is based on 'some facts' I will be relocating the tale to a fictitious locale with different names.
As a writer I feel I need to be true to myself, the period of time and to my characters. As one of the respondents on LinkedIn relayed: I'm wrote a Civil War story taking place in the South. Trust me, the plantation owners didn't say 'Get all them African Americans out to picking the cotton.' I sort of have to agree with him. Sanitizing the slurs will actually cheapen my novel and relegate it to obscurity since it won't connect with readers.
It was mentioned that some are attempting to re-write Mark Twain's tale to remove all slurs. Next we'll be re-writing Shakespeare to reflect today's slang... OMG!