Despite research to support that I think the problem might lie in that friendship may not seem worth it. Societies can emphasize individual independence, and technology can amplify it in real terms, making human interaction not necessarily where it once was. Why have lots of friends when so much of the immediately-obvious utility can be bridged by some other services?

Where neighbors used to possibly serve as an extension to your resources (a large ladder, sugar, someone to sign a package for you maybe), these days solutions (often technological) have sprung up to reduce the necessity of working together (rent-a-tool shops/sites, ease of transportation, configurable delivery).

Of course, the negative effects of restricted social networks are being felt now in communities (poor cohesion) and individually (mental health issues)... Tech helps sometimes (connecting people who might feel isolated in their immediate surroundings) and can hurt a lot of the time as well.

Yes, I think you're absolutely right. It's a combination of capitalism and bad urban planning (having to hop in a car to see people is bad for socializing since people are so lazy).

Anyway, what's the point of enjoying life if you die at the end? (I wish you a long and healthy life, just being pragmatic here)