In some ways freedom of speech can be used as a tool of surveillance. You say that people can say anything they want, and then you let them tell you who you should be watching via your sophisticated surveillance apparatus.
What it boils down to is that we don't censor things, well the reason we don't censor things is because our government does not feel the need to censor things to continue to function. That's because we have methods of dealing with people saying things that we don't want to become common opinion, i.e. we have very sophisticated propaganda tools to sway public opinion that until now were working pretty well. So we don't have to censor. Regimes where they don't have those type of tools have to censor, otherwise they lose power and legitimacy and things become chaotic. You can't control people.
To a Western secularist who basically has a covenant with the State called the Constitution, so it's a religious sort of deal. When the reason is not religious as to why states do this, they don't do it because they are bad or evil people. They do it because they feel that they have no choice and because that's how things in their country with their people.
For the Western States which have destabilized and destroyed many States in the Middle East using this sort of rhetoric, of saving them from a government oppressing its people, they don't have a leg to stand upon. They are not good because they are saving people from an evil dictator that does not follow their covenant. They are in fact at times evil and sociopathic in destroying and destabilizing those states that can not run properly without a dictator.
Russia is a country that heavily censores the internet and opresses its own people. That's a good enough reason.