I had a only a couple of good friends, but I had them for 10+ years. We'd stay at each other houses, spend time with each other's families. Play, watch movies, get into fights, goof around and so on.
Then eventually, as girlfriends came around, as we went to different universities, different countries, it was hard to keep the same level of friendship. First they become just "acquaintances", then sadly, they become strangers...
The point being, I think a lot of us know what the article means, it is just that we failed to hang on to it.
In America people just move more. It is hard to foster good friendships without face contact. Don't matter what the resolution of your Skype video, it is just not the same.
So, we are stuck. We'll end up spending more time on HN, playing Warcraft, working.
Another sensitive issue is that a higher proportion of HN-ers are probably introverts. Nothing wrong with that. I am one too. That means it is easier by default to be lonely. But in the long run it also hurts.