If free speech ever becomes suffocating, this means no one is listening to one another. Your utterances will reverberate off the echo chambers of one and the broadcasted paranoia of whoever will listen. And yet, all I hear is crickets!
This is, perhaps my favourite quote from Voltaire and one that we should all keep in mind. Best implies a limit, an unchangeable doctrine frozen in time regardless of the forme-function model of iterative improvement.