Sarah Tavel says she’s looking particularly closely at what she calls "Participatory Social" (e.g. Robolox, Fortnight, Discord) — platforms where communities and their members actually interact with one another, as opposed to Facebook where the model is based on content consumption.

To your point, I think if you’re building a vertical social network, you need verticals that are inherently social—that people like to talk about. Otherwise, it’s too hard to force connections and conversation around it