A lot of comments here seem to take as a given that banning any offensive speech in any forum leads inexorably to situations like this, where the "offensive speech" is political speech offensive to an authoritarian government. But this implies that it's impossible to distinguish between different kinds of "offensive" speech based on any meaningful criteria whatsoever, and this just seems to be fundamentally incorrect…
You should check out Schelling Fences on Slippery Slopes[1], particularly the section "Coalitions of Resistance".
There's also a separate disagreement which I have here, which is whether silencing people is actually an effective way to create change. It takes enormous resources even for governments to enforce it effectively, as we've seen with Nazis and the USSR in the past, and with China now. With bigots, censorship on other platforms has driven them together into some real cesspool platforms such as Voat[2]. I know for myself, having grown up in a homophobic environment, that the only thing that changed my mind about gay people was meeting and talking to gay people--a strategy which was explicitly executed by Harvey Milk in his coming out campaigns. Censoring bigots does the opposite: it drives bigots into echo chambers where they will only ever converse with other bigots who reinforce their views. In short: if you're censoring bigots, you aren't addressing bigotry, you're just sweeping it under the rug so you don't have to see it.
[1] https://www.lesswrong.com/posts/Kbm6QnJv9dgWsPHQP/schelling-...
[2] https://voat.co
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