“We should be eternally vigilant against attempts to check the expression of opinions that we loathe.”

― Oliver Wendell Holmes Jr.

It never was a helpful point of view; it was and is a cynical, sad, low side compliance moral principle. One might as well say: "You know, the government and businesses are not allowed to discriminate on the basis of race, but it has never been the case that I'm not permitted to be a racist in my own heart, in my own thoughts. I'm free to think that black and brown people are lesser humans." That is a legally correct statement, but abysmally immoral. Similarly, yes it is true that the constitution only protects my free speech vis-à-vis the government, but there has always been a prevailing ethos of free speech in America, in the spirit of the maxim often attributed to Voltaire: "I disagree with what you say, but I defend to the death your right to say it."

At one time it was a sign of a cultured, educated person that they did not bristle at the expression of points of view contrary to their own; they realized that in a pluralistic society we all have our points of view but no one can or should assume that their point of view should reign supreme. The increasing polarization of our society can be traced to notions such as this one expounded on Xkcd.