Moonlight, Lenny Kravitz, Imagine Dragons, Sam Fender, Massive Attack, ...
They are all okay names, but not the big names you expect at one of the biggest festivals in Europe.
If a band headlines a festival like the Lokerse Feesten or Gent Jazz just as well, then you simply have a band of that caliber.
Muse, Dua Lipa, Pearl Jam, or Rosalia won't be coming to play at a small city festival at this point in their careers...