That's not strictly true. If, for example, you have four management consultants, then they'll have at least six opinions between them. Which may well be the origin of the phrase: "What a load of arseholes".
Well, its certainly regarded as bad luck to mention the word r****t on Portland (Dorset) where yonks ago, burrowing bunnies were blamed for a major rock fall that killed dozens of quarry workers. Even today, that word, used in a local pub, will attract genuine hostility.