Locking someone up for disagreeing with you just highlights your insecurity. And I think the point here is that Facebook is a primary news source for many people. It may be enabling government censorship due to the company's monopolistic status.
Though I'd say the governments there are fairly secure. The Vietnamese communist party has been in power since 1945, China's since '49 and the Cambodian lot only got kicked out when Pol Pot, after having genocided a third of the population, attacked Vietnam who then invaded and got rid of him, and the new lot have been in power since 1984. Sadly throwing opponents in jail seems to kind of work. This of course predates facebook.
I did not comment on whether democracy or "democracy" is the best system for putting power at people's hands. That's another discussion.
My objections is whether we have actually been moving towards democracy or not. To just slap "democracy" or "republic" in the name of a state is not enough to make it so. It's how much autocratic the governors actually are and how much of the political decisions the population is actually able to define, that decides that.
In Greece, for example, government is in reality autocratic and people don't have much say. The only single check in place are the elections, but 1) You have to hope the other options are not just as bad as the current, which is unfortunately not the case, and 2) the established "aristocracy" has been doing a damn good job at managing people's opinions through the controlled media.