It was the same way in our neighborhood. We knew the names of almost everyone for at least two blocks in both directions. I watched a good documentary produced in England in the late 60's when they were demolishing old Victorian row houses in London to make way for big towers full of flats. It was heartbreaking to hear how people's lives changed after they'd lived in those flats for a year or two, especially the elderly. Human beings aren't meant to be cut off from one another like this and you make a good point about our devices. When you mentioned phone addiction I could help but how they effect us like those high rise towers, no matter what our living situation is like.
I witnessed this transition you mention. My family moved to a big apartment building following the big earthquake we had in 1977. All the other tenants were in the same situation and they brought with them the sense of community they had before. For a number of years it was all people being friendly, neighborly, but then people started moving in and the sense of community was gone. In her last years, my mother barely knew anyone in the building.
It's interesting that the first residents continued their socializing and sense of community even after their living conditions changed! I think the will/desire to engage in that has to be there, for sure.