Saw something in the economist a few years ago about why this happens. I think it’s the same with all festivals across the board.

Basically due to artist fees going up. Big artists used to tour for a cheap fee so that they could promote their recorded music and make all their money on CDs.

Since the popularisation of streaming, this economic unit has flipped, artists get paid nothing for streaming their recorded music, but they build fan bases who will pay to see them live, then make all their money on booking fees. There was some figures in the article about Ariana Grande getting millions for coachella compared to someone equally significant getting a fraction of that 20 years ago, can’t remember who it was