Millennial here - they definitely were real! Even back in 2008-2010 when I was in high school.
My kids don't know anyone or anything like that. It's so strange. They still have sleep overs where they play video games and use their phones. That's fine in a way. At their age I was in the woods getting drunk and starting bonfires. It was fun as hell, but maybe something closer to the middle would be ideal.