"Tankie" doesn't mean anything, and neither does "authoritarian." All states are authoritarian. Most people in the core of the capitalist-imperialist world system who talk about DPRK as if they know anything about it are in no position to do so. Most of the information they get about the DPRK comes down from so-called defectors. Those defectors are usually people who are captured by South Korea with the use of the imperialist National Security Act, which was instituted by the USA back in the Korean War to divide Korea and protect American imperialist interests and the right-wing government they installed there and so on. They place people from the DPRK in solitary confinement for months on end and turn them into anti-DPRK spies and propagandists, only releasing them until they are fully brainwashed against their own home country.

There is no basis for believing that the DPRK "forces" their people to procreate.