The median new home size skyrocketed in the '80s.[1]
Many of the post-war suburbs were planned communities built with schools, churches, grocery stores, and other necessities within walking distance.[2] Compare that to developments today (and since the '90s), that are all housing, lack sidewalks, and require a car to get to necessities.
Serendipity doesn't happen when everyone's in cars. You don't pull over to invite an acquaintance over for a beer or offer to watch their kids.
Good point. Car culture was nonetheless a thing even in the 70's though where I grew up up. And those 70's suburbs are still there. So I am not sure why they are still not partying in Overland Park and Prairie Village, Kansas.
I almost never meet people who like the same bands as I do. I can listen to new music that I love at home. If I go to a bar or a party I'm going to mostly hear music I don't like, and if I do like it, I could have already heard it at home.
My own personal theory? Music sucks now, ha ha.