That proof doesn't hold as an argument. You're arguing that if people got a message out then it isn't cancel culture, but if people didn't get a message out because they were cancelled then people just wouldn't talk about it. It is setting up a rhetorical position where taboos can't exist and we know that they do.
Cancel culture might not exist depending on what people think it mean. The term is a bit vague. But arguing that some people managed to push past the cancellation attempts doesn't mean that there isn't anything there. We'd expect cancel culture to have some cancellation attempts that ended in failure, the authoritarians are fallible humans too. And although they tend to be good at wielding government power the extreme authoritarians do tend to be ideologically isolated and so struggle to act when people pay attention to them.
Look, "cancel culture" is almost as vague a term as "communism" and tends to be used in the same way: as a thought terminating pejorative description for anything someone doesn't like.
If we want to have an actual conversation about it we'd have to come up with some kind of working definition of the term that was actually useful enough to discuss existing examples with.
The wikipedia article on cancel culture uses an example of people disassociating from harvey weinstein and ultimately charging him with crimes related to sexual abuse. Is this cancel culture?
If a university employee invites a celebrity to come give a lecture one evening and then a bunch of students ask the university to cancel the invitation, is this cancel culture? Is it morally wrong?
Is the person who makes the original statement deserving of some kind of extra protection for this speech over the responding person who is trying to criticize this speech?
A cursory look at the real world, actual examples, of how people attempted to use the term "cancel culture" it was invariably part of an attempt to prevent criticism of (mostly) right wing ideas.
What actually happened was some number of right wingers tried to give speeches and got yelled at and then started complaining about cancel culture and trying to prevent future criticisms.
Like, at the level we're discussing we're talking about things like ethics/morality/social standards, right? What is good and virtuous for society to permit and encourage. Trying to "cancel" people who are "bad" by using speech to criticize or contradict or even ask people to stop associating with them is a good thing.
That proof doesn't hold as an argument. You're arguing that if people got a message out then it isn't cancel culture, but if people didn't get a message out because they were cancelled then people just wouldn't talk about it. It is setting up a rhetorical position where taboos can't exist and we know that they do.
Cancel culture might not exist depending on what people think it mean. The term is a bit vague. But arguing that some people managed to push past the cancellation attempts doesn't mean that there isn't anything there. We'd expect cancel culture to have some cancellation attempts that ended in failure, the authoritarians are fallible humans too. And although they tend to be good at wielding government power the extreme authoritarians do tend to be ideologically isolated and so struggle to act when people pay attention to them.