Sourced? From what? Propaganda, opinion pieces, and almost the entire library of Marx and Engels?

You know other people can have input on the economic state of "communist" nations outside of those nations right? This essay is the equivalent of those anti communist propaganda works from the height of the cold war.

Or they read enough to not fall for the propaganda

If it's something you believe is true then you should be able to articulate it and use it in arguments. If you're not able to make an argument in favor of it then you are either holding the belief disingenuously or don't know enough about what you're arguing about