Facebook, Instagram, and Snapchat are all warrens. Twitter is a plaza.
https://www.ribbonfarm.com/2010/10/27/warrens-plazas-and-the...
Even 5 years ago it wasn't clear whether warrens or plazas would win. They were betting human behavior would change under different constraints -- maybe we'd move beyond our tiny friend networks, come out of our warrens, and have a global party in the plaza. It looks like either we're not ready for that yet, or we'll never be ready for it, because it's suboptimal.
That's not to say plazas don't have their place. It's just that right now we prefer to spend most of our time in the comparative safety of the warren.