Sitting in a field isn't how I want to consume my music, but large or small, I think festivals are a great thing. I'm playing at a couple of local festivals next month. Friends went to Glasto every year for decades. They went for the experience as much as the music.
The last big festival I went to was Reading 1973. I'm afraid I can't take most of the DJ/presenters on the TV coverage of Glasto, so I don't keep up with who's appearing.