I think the elephant in the room for making new friends over 30, is stagnation in one's daily routine caused by one's job.<p>I don't think anything changed dramatically in the last 60 or so years on this point, even with the development of social media; by the time you're 30, you're basically done making friends.<p>The article glossed over it, but in your childhood and teens, you're surrounded by a new group of people every 5 or so years, and just through sheer quantity, you're likely to make at least a few friends. Throw on team sports, extracurriculars, clubs, and the ease of introductions in a school environment, and it's almost impossible not to make a few friends all the way into your late 20s.<p>Somewhere around when you turn 25 or so, though, without substantial effort, things stabilize. If you were going to leave your home, you probably did, and you're settled in. You and your old friends start to marry and have kids, and both of these occupy your free time (and theirs). You may have bought a house or found a job you want to settle into for a while, with plans to stick around for several years.<p>For at least 8 hours of your day, you are at work, interacting with people in an environment toxic for creating trusting friendships (You're competing for the same roles, titles, bonuses, etc.), and worse, these people you're competing with are almost always the exact same people, so if you're not really friends with any of them immediately, that's basically never going to change.<p>With the remaining time in your evenings, you'll also settle into a routine. You won't be playing sports anymore, and if you have hobbies, you'll generally be doing them with the same small consistent set of people in your area, assuming you do them with others at all.<p>So, in short, if your 8-hour workday isn't a time to make friends, and you're not interacting with people in a way that leads to making friends in your 8-hour evenings, when the hell do you expect to be making your friends over 30, during your 8-hours asleep?