Free speech, no matter where you are or what the platform.
No, free speech does not mean anyone needs to provide you with a live-stream, forum post or blog page. These are private spaces, open to the public, like malls, rather than parks. They're privately owned and controlled.
In the public realm, on the "commons", no one owes you a soapbox, a crowd, or any attention, either.
It just means you can stand on street corners with a sandwich board, or hand out leaflets or visit Speaker's Corner in your nearest park without the threat of violence or restraint. It doesn't give you the right to step into traffic or obstruct or harrass people, though. If you want to stay on-line where the people meet, you can run your own Web site, or send out e-mail newletters. Speech is made of words, not actions. Arguments are won with facts, not fists.
If you don't have free speech, then first you may need to reform or overthrow your government. This may involve loud, disruptive protests and is legitimate. This is where the CCP falls down. By suppressing free speech and democracy, they legitimise revolution.
Is any wonder that such protests take place on on-line forums...
No surprise that people try. Just don't expect corporates with competing loyalties (e.g. profit) to provide those platforms freely.