Comment by Desafinado

It isn't so much about the smartphone replacing family as it is about phones giving us something to do in our homes in lieu of the presence of other people.

Even a family that lives close to each other is separated in space by different homes and will often find themselves alone. But their situation will be much better than someone with no family around. They have the option to see each other, many don't.

I think the more detailed point is that we're largely atomized these days into separate physical spaces where we're often alone, or confined to a small number of people. Smartphones and computers make it a hell of a lot easier to break through that problem.