The second law of thermodynamics does not seem to apply here. Without a source of energy entropy must increase. Using the second law as an analogy of the information situation in China one would say you are correct if there was no external entity actively trying to suppress information. But there is in the case of China. Thus the second law analogy does not apply.

It most definitely does apply here.

"Entropy may be understood as a measure of disorder within a macroscopic system. The second law of thermodynamics states that an isolated system's entropy never decreases. Such systems spontaneously evolve towards thermodynamic equilibrium, the state with maximum entropy."

They aren't able to suppress information completely which is why they resort to the sort of shambolic behaviour described in the article. They lost control of it when the internet became widespread and since then they've been trying their best to firewall and block and censor, for what? Why censor anything if there is no appetite for it anyway? We can assume therefore that there is some percentage of the Chinese population that wants to know and will know despite their governments efforts.

From what I read (no first hand experience, and based only on relatively shallow news & nonfiction reading), the CCP's aims don't rely on complete control of information. They want political control of the public sphere, for which purpose all they need to do is keep infractions below the surface. There's a nod-nod-wink-wink with the emerging middle class: "pretend in public that everything is as the Party says, whether you privately believe this to be true or not, and we'll deliver the goods". They don't require loyal hearts, just broad obedience.

What they're vulnerable to isn't information leakage, but a future failure to deliver the goods (in which respect they're not that much different from liberal democracies). So far 3 decades of predictions that they would fail to continue holding a lid on the public sphere, and 10 years of predictions that they would fail to deliver the goods, have all been wrong. Which is unsurprising given that those predictions were rarely based on anything more substantial than a priori and ahistorical liberal dogma.

In terms of the analogy it’s not an isolated system. There is an energy input; the active suppression of information. Therefore the second law does not apply.