I dont know the solution but few things that are root cause:

- Internet and Social Media

- Neighborhoods no longer are walkable especially suburbs at least in America. Kids are not encouraged to go bike to their friends place anymore because of traffic risks.

- High Trust societies have degraded into "lets keep ot myself, I can't trust anyone these days". Decades ago, you could just walk into a neighbor's home and say hello. Now, you need an appointment just to talk to a neighbor or are too worried what they will think of you.

- No real friendships after school/colleges. This is a huge deal once you are out on your own in the real world. Work relationships are meh at best and with remote work nowadays, it has become even worse.

- Even if you join a club or activity, they are too "planned" and "robotic". For example, my kids take a dance class and they said they don't like it. I realized why. There is no break. They don't even get to spend like 30 mins with other kids socializing etc. There is a fixed schedule. You go, you dance, you leave.

But this is the world today. So I don't know how to fix it.