Rae Langton on Talking Politics (back when it was called Election):
Often one finds in discussions about bad speech is that [people say] "You should, of course, let people speak" and they just think bad speech can just be driven out by good speech. I would love it if that were the case. I am dubious that we have the conditions where that is going to hold very easily.
How often has some Nazi been profiled by a journalist, who then provided equal time to good speech? Good speech is "boring" now to many journalists and does not get clicks. The dapper "exciting" Nazi profiles don't bother with that.
In practice, speech is free for speech that sells or interests the powerful.