After the Portuguese Boom Festival cancellation, German Fusion is another festival to be postponed to 2022 due to the ongoing pandemic (and bureaucratic measures), while German ZEIT magazine quotes a study by World Health Organization WHO that the pandemic could have been prevented. Apart from few exceptions like New Fall Festival, that will be held as a seated “Summer Edition” (like in 2020) in the courtyard of NRW-Forum Düsseldorf, most summer festivals seem to have been cancelled already (as of May 2021):

Fusion Festival Absage – Kulturkosmos Newsletter Mai 2021

Fusion-Festival 2021 findet nicht statt (FAZE Mag)/

Boom Festival 2021 rescheduled to 2022/

WHO-Bericht: Corona-Pandemie hätte verhindert werden können (Die ZEIT, Mai 2021, in German)