The distinction in this case is that 8chan is simply a “poisoned well” which can be boarded up until the next one takes its place, whereas “Islam” is a whole ideology followed by a billion-odd people.

“Extremist Islamic terrorists” on the other hand, that is a narrowly defined enough population to feel justified in going to war against.

But the point is, no one’s speech in particular is being suppressed. To keep the metaphor, a “mosque got too radical” and was shut down. People who were practicing there will have to find another place to go.