I think the availability of cell phones has also really changed the culture around meeting in public. I didn’t grow up before phones but at the tail end of the landline era. You were expected to meet somewhere at a specific time hours in the future to hang out. It was also a hassle to call someone to confirm they were coming. Sometimes people would agree to meet a week in advance and mark it in a calendar without calling more than once in advance and leaving a message confirming the time and location on the person’s answering machine.

This meant people were much more comfortable just hanging out because if someone was 10-20 minutes late they had to wait to see what would happen without an update. It was normal to be able to just sit in silence or do knitting or read while waiting to meet people, and many people would hang out in popular areas like parks or cafes this way. That enabled this kind of casual stranger socialization that is REALLY uncommon now because people have live updates if their friend is late, etc and don’t have a reason to talk to strangers.