Censorship always starts with unpopular speech. Historically it's been raunchy porn, religious blasphemy, and direct opposition to the state. Hate speech seems to be a new one that works well to sell censorship to liberals (who should know better).
In reality, it's not state sponsored censorship at all, and it doesn't lead down any slippery slope.
These claims of censorship are extremely selectively applied, to only certain types of political speech. I wonder why that is?