It was never about a long, entertaining performance. In Ye Olden Dayes, it was about seeing as many up and coming bands as possible in a few days time. Exposing bands to audiences and audiences to bands.
I don't know if that's even needed now in the age of youtube.
If it is of any value still, it needs to be as well-curated as it was back when. It doesn't seem to be any more.
Really, what is it about a "Music Festival" where a band gets 30 minutes of stage time (if they're lucky)?