Generally speaking, plaza are public while warrens are private. Plaza are easy to expand, because people can see what is going on in the community and decide whether to join the community. On the contrary, warrens are personalized contents in social network, which makes they scale free. Therefore, communities that have a plaza-like structure are easy to expand, thus suffering more from Evaporative Cooling Effect, while communities having warren-like structure are not very scalable, but more stable. A successful social network should somehow combining those two structures, taking both scalability and stability into account.

Venkatesh Rao thinks that the Nazi bar analogy is “an example of a bad metaphor contagion effect” and points to a 2010 post of his about warren vs plaza architectures. He believes that Twitter, for example, is a plaza, whereas Substack is a warren: A warren is a social environment where no participant can see beyond their little corner of a larger maze. Warrens emerge through people personalizing and customizing their individual environments with some degree of emergent collaboration. A plaza is an environment where you can easily get to a global/big picture view of the whole thing. Plazas are created by central planners who believe they know what’s best for everyone.