Actually, Rippon notwithstanding, it is not a dictionary that decides if a word or phrase is offensive. That is decided by how people use it. In linguistics, such terms are called taboo words. All of the terms you have mentioned are considered taboo words because they are offensive to a wide variety of people, including probably the vast majority of those who frequent the BB (including me).
As I said before . . .
"What makes a cuss word a cuss word is usually the other person who takes offense."
Which is what you said, but your intellect/bias may prevent you from understanding.