Re: Wouldn't this just create more North Koreas?
I'd argue it likely wouldn't for two reasons, the first is that the disruption to business would likely chip away at the support of, and hopefully bring down, the offending governments, before they ever got that far. Governments restricting and censoring the internet in this fashion would usually be well on their way to becoming authoritarian, if they were not already so. They still, however, need the support of broad sections of their populations to stay in power. Severely harming business interests could radically reduce their support in several key support bases, the business community most directly, the general population (by way of self-inflicted economic damage), and possibly the military, if the general situation deteriorated that much (i.e. increased disorder, and possibly fewer resources going to the military).
The second reason, related to the first, is that these countries would generally not have a Chinese "sugar daddy" to prop them up, as North Korea does now. North Korea is not a normal state; it exists as it does today only because China views them as a useful buffer/client state between themselves and capitalist South Korea, and it's thousands of US troops. The removal of Chinese support, and most importantly money, would collapse the North Korean regime quite quickly.
You might argue that these sorts of policies are unfair because they will harm the populations of any countries that might run afoul of these policies. The populations of these countries are, however, already being harmed by the policies of governments that policies such as these are designed to combat, both now, and in the long term. I'd argue that countermeasures such as this would only make it easier for all to see how widespread censorship and similar policies are ultimately self-harming, and the only people they serve are a handful of kleptocrats who want a slightly easier time of it in robbing their people.