A friend who used to run big late-night parties in San Francisco said the big change started after the 2008 recession. Many of the twentysomethings who were laid off left town, and the ones who remained were working longer hours.
I was on the scene in the Bay Area in the 2000s. I went to warehouse parties and secret raves that required calling a number to find out where to get picked up to keep the location secret. It was vibrant and a lot of fun.
There were at least two sites that I knew of for keeping track of parties (bayraves.com was one, I don’t recall the other). The scene was dying at the same time that I was aging out, but I sure miss it.
When I lived in the Midwest, the scene died when ecstasy became a known quantity in mainstream news media. The last rave that I went to (there) was loaded with a million cops. An org that offered free testing for purity / adulterants was told they’d be arrested for testing any pills. What a backward and unhelpful position to take when people may be at risk of an OD. Ecstasy was still generally clean at the time. I’d be afraid to take an unknown pill today, what with fentanyl and the like.
My wife, who has been a raver since the 90's, is currently out collecting free Narcan doses to deliver to people throwing raves in Southern California. Party organizers need to really step up and have Narcan on hand, but most don't.