I cant read past the first paragraph because of paywall. If the author hasn't come to the conclusion that it's because of all the fucking cars they need to reassess.
Walking to places and randomly running into people who can become acquaintances, then friends is difficult or impossible in places with cars as the primary transport.
Meeting in 'third places' is no longer easy because all of those areas are gone or dying due to car based infrastructure.
Town and city public meetung spaces are dying or gone due to car based infrastructure 'needing' those areas for parking.