A well-written post. Some highlights focused on the network angle of things:

The old neighbourhood was not a collection of individuals who happened to live near each other; it was a living organism with its own immune system and its own way of metabolising change. When Moses bulldozed it, he killed a community and scattered the remains.

Jacobs understood that the value of a community isn't in the people as discrete units. The value is in the specific, unreproducible web of relationships between them. You can move every single resident of a street to the same new street in the same new suburb and you will not get the same community, because community is a function of time and ten thousand microtransactions of reciprocity that nobody tracks and nobody can mandate.

What Dunbar's model implies about community is underappreciated. If a community is a network of overlapping Dunbar layers, then each member's experience of the community is unique, shaped by where they sit in the web. There is no "the community" in any objective sense. There are as many communities as there are members, each one a different cross-section of the same social graph, and this means that when you lose members, you lose entire subjective communites that existed literally nowhere else.