Whoever is in power determines what is "ethical society" or what makes society "better". Censorship is a form of physically violent oppression and is never justifiable.
Free speech is an amoral tool, which can be used to improve or degrade the human condition, when wielded appropriately. It's our job to decide when and how to use it, and not act naïvely and pretend it's a virtue in itself.
Soviet censorship vectors were able to wrap dissenting viewpoints as "counter-revolutionary" or "bourgeois" without regard for the consistency of content to the wrapper.
Or do you mean to say that isn't censorship?