My honest take on her music is that I don’t think it lends itself well to a headline slot. She has some decent songs, but the ones I listened to all had a very chilled out vibe. I disagree that the Pyramid stage was the wrong stage, she could have worked that stage well, but in an earlier slot, her music is the kind thing I’d love to stand and listen to during a nice sunny afternoon slot.
I just don’t think it’s headline material, whether Pyramid stage, West Holts or Woodsies… And that’s nothing to do with popularity, she’s clearly massive with certain demographics, it’s a vibe thing. By that time in the evening, much of her usual demographic are well into party mode.
Again though, to be clear, I only listened to her 5 or 6 most popular songs 2 or 3 times, along with the obvious SM viral ones countless times, so I’m basing my opinion on very little data. If she does have some more upbeat music in her catalogue I apologise.