That said, I wonder if an argument could be made that the B-word is a form of hate speech against a protected group (women) because it is dehumanizing (compares them to an animal in a degrading way).
In the private sphere, Facebook says it treats such speech as Tier 1 hate speech (see https://www.facebook.com/communitystandards/hate_speech) although I don't know whether it treats the B-word as qualifying. (I would argue it should, based on FB's own definition.)
Granted, hate speech is still protected by the First Amendment. So there are no legal penalties in the U.S. for using it.
But I wonder whether treating the B-word as hate speech in terms of our cultural attitude toward it might make its use less common.