Until conveners and organizers discover what it means to design gatherings for building communities and networks, they naively believe speaker or entertainment based events can do so. They don't because they can't. People congregate with familiar people talking about familiar things. The worst scenario is when people don't interact with each other at all because they're all passively listening to or watching others talk or entertain.
Existing connections don't deepen and new connections don't emerge. This only happens when gatherings are specifically structured to make these possible. This happens when we invite people to name new conversations and invite others present into them. It happens when we have network weavers present actively connecting people who don't know each other, making rich introductions and inviting connecting conversations. It takes a whole different kind of social architecture.