The whole idea of words being offensive, I find somewhat ironic. The "N" word, as some like to refer to it, was not originally an offensive or derogatory word and, in fact, derived from the same Spanish word for "black". It's just that the people of the time were lazy in their enounciation and mispronounced the word and later it did become a derogatory word, not because of the word itself but because of the attitude of the users of the word.
In a similar way the perfectly good word "Queer", meaning odd or unusual, became derogatory because of the attitude of the people using the word and how they applied it. I regret that so many good words are no longer available for use in their original meanings because of "political correctness".
Another example of "political correctness" vs. "attitude" is the book entitled, "Little Black Sambo". This book was not even about a person of the Negroid race but was about an East Indian boy. But the use became so politically charged that a local restaurant founded by two men named Sam & Bo had to change the name from SamBo's to something less offensive.
As for what our grandchildren may find offensive in todays literature, just think how offended our grandparents would be offended by, what to us is rated PH-13, but to them would be considered too sexually explicit.
Bottom line, IMO is that it is the attitudes of people, not the particular word used that should be critized. I really became aware of how any word should be considered Ok when used in proper context back when I was 30. In a public park, where a dog show was taking place (I was there just enjoy the park), they announced over the loudspeaker, "The showing of the bitches will be at two o'clock." I actually physically cringed because they had used the "B" word on the loudspeakers. Later that day, after careful consideration, I realized that it was a proper usage of the word and made me begin to examine my own attitude and how I used words. I now try to use words properly, whether they are PC or not.