Words become more acceptable over time. In centuries past calling someone a devil or saying that they should go to hell would have been deeply offensive. Today these insults are so mild that even schoolchildren say them to each other. Even twenty years ago the word “fuck” was viewed with nearly as much taboo as racial slurs. Now, it’s a very common word that people will throw around in a casual context.

Even the word n****r (means “black person”) and its non-hard-R variant are starting to lose their offensiveness. In African-American Vernacular it has taken on a variety of inoffensive meanings. It is now only offensive in certain contexts while fifty years ago it was pretty much offensive in all contents.

At the same time, new words emerge and get labelled profane. For example, the word t****y (means “transgender”) would not have meant anything twenty years ago, and now it’s one of the most offensive words in the English dictionary. Similar story with the word f****t (means “homosexual”).