The 5 Lollapalooza Performances That Best Showed Us Where Music Is Going

By the time Sienna Spiro walked onstage Saturday at the Airbnb stage, it was already clear the booking was wrong — not in a bad way, in the best possible way. The crowd had outgrown the stage before she even sang a word. People were standing three and four rows deep past where the crowd was supposed to end, craning over shoulders, pulling out their phones just so they could see. She’s 20 years old. Her debut album came out this summer. And Lollapalooza put her on a stage that, by the time