Who Was the Heavy Metal Band at Opening Ceremony? That Was Gojira.
New York Times
Gojira, a popular French band, became the first hard rock act to perform in an Olympic Games opening ceremony when it did a metal version of “Ah! Ça Ira,” a song that was popular during the French Revolution.
https://www.nytimes.com/article/opening-ceremony-heavy-metal-band-gojira.html