They are closely related though. Mass surveillance, and/or the loss of privacy online, has a chilling effect - effectively censorship.
Either your government blocks / censors your er, controversial statements, or you're afraid to post your controversial statements because the government is watching you. Same effect.
China blocks access to anything on the internet that disagrees with their ruling party. They block any VPN or SSH. Like, not just for avoiding filters, just at all. They degrade any encrypted traffic by just doing compression analysis and dropping packets if your traffic looks encrypted.
This is not the same thing as the NSA’s dragnet surveillance or anything the UK is doing. China is already at the endgame you are hypothesizing, and you’re creating a false equivalency through a slippery slope. A slope where the bottom is where China is today.
Either your government blocks / censors your er, controversial statements, or you're afraid to post your controversial statements because the government is watching you. Same effect.