An offended person’s decision not to speak is hardly a reason to suppress the speech of others. Those who find an idea, epithet, literary work or other form of expression offensive can oppose, counteract and perhaps refute it with further speech not by banning the speech deemed to be offensive.
As Justice Louis Brandeis said in a famous quote, "If there be time to expose through discussion the falsehood and fallacies, to avert the evil by the processes of education, the remedy to be applied is more speech, not enforced silence."