To counter your easy dismissal I'd say modern individuals, rife as they are with selfiness, consumerism, lack of empathy and of time to connect to their neighborhood, are mostly basing their circles on career paths and personal interests, and other people being their cultural split image.
What both arbitrary socialising and consumerism have in common is that they are focused on selves whereas truly important activity primarily relates to abstract ideas. It is ideas that create the solutions to local problems.
Btw, none of this is inconsistent with a smile and a nod to people you see about you in daily life! And mingling with new people if one feels lonely.
It could be the other way around: we are born into families and nations and therefore we post-hoc accept and value them.
We can't wait to leave and get away to the big city and then, eventually, from time to time, we yearn to return home. Not due to some innate preference or unexplained genetic mechanism but simply because that's how we grew up.
However, few are willing to give up their new-found freedoms for a circumscribed tribal existence. Which doesn't mean we can't or shouldn't honour our pasts.
I've never really been comfortable getting to know my neighbors. I feel like they see and hear too much about my private life as it is, it's actually awkward for me to see my neighbors.
I don't know about you, but I find watching a movie or sitting around a fire with my neighbors far more therapeutic than text messaging on my phone.
Really, with current online life, people have contact less with random strangers and more with like-minded or otherwise interesting individuals. If in an [abstract] countryside you have to talk to you neighbors because there's no one else around, on the Internet the choice is wider.
OTOH your neighbors may be nice and interesting people; some of my neighbors are. Also you might have some local common interest, or could e.g. lend power tools or kitchen utensils to each other sometimes.
Not to mention the internet tends to form echo chambers. It's good to meet people who are not like-minded...
People forget that 100 years ago that wasn't really an option.
BTW, the telephone was invented nearly 200 years ago. Although, yes, travel options were more limited.
And yes, meeting people that are not like-minded is very important; is it beside a fire or through a glowing screen, does not matter.
Do you just ignore the people you work with as well for similar reasons?
OK, one reason off the top of my head. Say something suspicions is going on outside your flat. Someone that could be checking out your house wanting to break in. A friendly neighbor may go up and ask in a non threatening way if you were expecting to see John in just now, and could he take a message for you. Ignore your neighbor to the point he doesn't even know your name, and guess what. He won't give a shit. Which scenario is more likely to get your place broken into?
It's propaganda disseminated by unhappy single women. :) I said it that way because not all single women are unhappy -- some prefer being alone, just as some men do. Recent statistics tell us that almost 1/2 of Americans are single, and they're about to become an absolute majority.
Maybe they're completely boring. Maybe the person under discussion prefers being alone unless and until the entire neighborhood is going up in smoke. It's not as though large groups of people are what nature has in mind, regardless of environmental and biological changes -- evolution doesn't work that way.
About 1/2 of Americans are now single. Is this a disease, or a result of personal preferences, by people who tried the alternatives and then made the least objectionable choice?