Because if you spend enough time on the internet, especially the Western side, you start to hear voices of people who oppose their governments and not enough from those who support it.
Even many who are supportive tend to say that their government is authoritarian.
Authoritarianism isn't real. Every state aggressively defends its class base. If you don't face repression from your capitalist country, that says a lot about how the state sees you.
These socialist states aggressively defend the project of socialism in their countries because it represents the working classes.