It's not even about the general public, it's about the state apparatus itself. All institutions have a certain internal logic, and even though there's plenty of room for dissonance between the official truth and the understood reality, it has limits. Either real reform is limited, or the institutional logic is reformed such that it can remain functioning, and if reform is necessary, then the latter is the only option. (China represents an example of success, the fSU, I think, an example of failure.) This is impressionistic, granted, but I'm sceptical of the ideological flexibility of Juche-Songun and of the ability of the current rulers to handle such ideological reforms, so the only way I can see any sort of political reform happening is with a pretty major ideological shift. Perhaps we'll see a Deng Xiaoping emerging, some individual or faction that guide the DPRK through a middle path, but I don't think it's likely.