Cuba, the case I'm most familiar with, it's very interesting because (so far) it doesn't limit much the access to outside information using the Internet[^2], but only official newspapers, books, radio and TV programs are allowed.
I have this view that the information that the citizens of a country consume is like the regulatory signals of an organism. For a healthy organism, those signals must be coherent, otherwise some terrible disease will consume the organism.
Of course, as a creature of the enlightenment, I hate that notion. I want my information to be free.
But in the big scheme of things, the way I feel about it just doesn't matter. It's enough that states that police the information their citizens consume live longer than states that not. How to get from now to then is an open problem in some cases, but everybody is trying. CP and terrorism, and the vague term of "national security," are the vanguard which is being used to rive down the door on privacy in the Western countries, though the battle is already lost in much of the rest of the world.
[^2]: Except on those occasions when the citizens actually dare to riot, e.g. https://en.wikipedia.org/wiki/2021_Cuban_protests#cite_ref-1...