No, it’s not. You shouldn’t have to muzzle your opposition to feel safe, or to threaten them with jailing to feel like your ideas are being heard. That speaks to some pretty deep seated insecurity if you feel that way.
The comment is not excusing censorship, but illustrating that censors don't like to call what they do "censorship". Even a justification for it is not enough - they don't want to call it "justified censorship", they want to call it something else entirely, and even then they want as little attention paid to it as possible, to trick people into thinking their discussions are free.
> Does this advice apply in every case or does it have a restricted scope?
In case you’re being serious, this has been debated in various liberal traditions since the conception liberalism was first born. In essence, the modern liberal tradition (modern as in post-Enlightenment, i.e. about the whole time America has existed) says you don’t censor anything except for forces seeking to censor (paradox of tolerance).
So now every force seeking to censor will just say its opposition is a force seeking to censor, and get them censored. Like how the Nazis claimed the Jews were the ones destroying Germany, then the Nazis destroyed Germany. How do you stop that?
Better minds than mine have debated the paradox of tolerance (a name only given in the 1950s, but a concept recognized for longer).
Also, not tolerating something doesn’t mean forcefully censoring it. Norms and conventions largely keep e.g. frowned-upon slurs out of common usage. The person getting told to shut up for using the N- word isn’t being censored by the state, but they are being encouraged to engage respectfully.
In practice, it seems that whenever someone is told to shut up for using the N- word, they react by saying it many more times. So it doesn't work very well.
> whenever someone is told to shut up for using the N- word, they react by saying it many more times
One, not my experience. (Indian family.) Two, people spouting out the N- word have generally caused themselves to be ignored, which sort of solves the problem as well.