I don't disagree with the sentiment, but I reject the premise that my free speech rights are contingent upon someone else thinking the content of my speech has some valid purpose.
Don't you think freedom of speech has a valid purpose? There needs to be a vigorous defense for freedom of speech, including more controversial speeches like blasphemy, etc.
The primary benefit of free speech is not having to entrust the policing of speech and related enforcement to anyone. It also helps to identify the idiots.