You do have a kind of censorship - the media promote mis-information as truth and then people, who for some reason like to be misused by misinformation, make a lot of noise shouting the lies repeatedly, these are the right wing and some Liberals. You don't know the truth about anything much - any more than the Chinese population do, you (we) have an illusion of free speech.
As for some of the censorship - I find it hard to argue against stopping pornography because it debases and devalues people in the making and in the watching. The social sites are used by outside sources to interfere in Chinese internal affairs - some of these could be justified as everything is not perfect here, but much of it is just malicious lies and fabrications. Separating the truth from the lies is as impossible as separating them in the western media - simply blocking the sites and news sites is a crude way of doingthe job. Also it is very easy to get around if you feel the need, up until recently the sites that allowed us to do it were free, now they charge and I don' tneed it that much 
By the way I am English - just living here teaching - and writing about China and the West in general.