How uncensorable is #Nostr ?

Would you recommend it to an activist in China? Cuba?

Please provide as much evidence and reading material as you can in your answer. Building a free speech platform is important. There are 100s of platforms that claim to be "free speech", none are. Nostr seems to be the closest thing we currently have... but I'd really like to see steelman arguments for and against.

I will zap ⚡ the best answers.