I would argue that Minecraft’s sensational and enduring popularity isn’t despite the fact that it is not open source, but because it is not open source. Open source is not a panacea — far from it. An open source Minecraft, would likely, in my opinion, devolve into something akin to Calvinball, where the only rule is that there are no permanent rules. A closed that system that encourages and enables a rich amount of user-hackery within a set of reasonable constraints is almost certainly more fun and rewarding than an anything-goes free-for-all.
it’s an interesting take on Minecraft’s success, and more fuel for the argument against the idea that open always beats closed. Minecraft works because it gives creators a framework to work within. If creators had to create the frame themselves, it would probably collapse.