I’ve spoken about it in other threads, but I believe that a significant factor in the the weakening of neighborhood community is the need for people to move frequently (relative to the past) to have access to opportunity (whether it be education, employment, or something else). Each move means a total reset of social connections for the individual moving and a hole left behind in the community being moved out of. Eventually nobody in a neighborhood other than a handful of longtimers (likely retirees) knows each other and everybody is a stranger.

I think it would do an immense amount of good if employers in particular made greater efforts to allow employees to stay where they are, whether that be through small satellite offices or remote work.