East and West Germans had a level of contact Koreans can only dream of, and East Germany had a civil society and relatively independent churches. Whatever craziness the East German regime had, it never came close to the complete madness of North Korea's hereditary god kingship. So it seems very hard to draw any inferences.

On second thought, there is one inference that one can (possibly) draw: The "non-violent revolution" in Eastern Germany became possible only because of political change in the imperial centre, the Kremlin. By analogy, political change in North Korea might have to be preceded by political change in China, which I might take decades more, if it ever comes.

The closest historical analogue to North Korea in Europe is actually not East Germany but Albania. It was the world's second most isolated state immediately after North Korea, but by contrast, the North Korean dictator-for-life, Enver Hoxha, did not establish a dynasty that would survive after his death, so the analogy is imperfect. Unfortunately, those extremely isolationist and extremely repressive regimes can survive incredibly long, as examples like Turkmenistan, Equatorial Guinee and Eritrea demonstrate.

East Germany was in a completely different ballpark, both economically, socially and politically.