I agree that some forms of cancellation are illiberal and anti-free speech. But a lot of the time, what gets called "canceling" or "shutting down" are themselves forms of free speech and freedom of association. Freedom of speech doesn't mean that everyone is entitled to being taken seriously, or having their opinions broadcast in private venues and publications, or being immune from criticism, mockery, protest, or social ostracization. A lot of people who call themselves free speech absolutists think that none of this should be allowed and that all ideas deserve an equal hearing.