Everything has a cost, the cost of free speech is the possibility of hateful and destructive propaganda. This cost is in my opinion trivial compare to the alternatives. We saw what the cost of speech and information restriction have done to civilizations in history.
The ability to speak freely and having access to information is not just one virtue like justice or compassion. It is the way by which we create our value.
We should take really seriously any attempt by anyone to restrict it.