BTS talk 'Dynamite' No. 1 hit achievement, thank their Army fans and look to the future https://t.co/sfl6CsB3qg— USA TODAY Life (@usatodaylife) September 2, 2020
-- Though BTS said in 2019 that they didn't plan to sing in English because they didn't want to change their "identity", they cite the global COVID-19 pandemic as the reason for their change of plans, and say that creating the song was "like destiny."
RM: "Who would ever think of this pandemic? No meeting, no karaoke, no concerts? Even no walking in the park. So we never expected this song would come fully in English. During the process of making our album … it just came to us."
-- However, David Stewart, who wrote and produced this week's number 1 on the Billboard Hot 100 along with Jessica Agombar, had this to say to Rolling Stone:
“They were looking for an English single; it had to have tempo, be exciting, and one thing I’m good at is writing to brief.”
-- Earlier this year, word spread through the music industry: The star K-Pop group BTS was looking for a new single. “It was a bit of a holy grail cut, I had quite a few conversations with big producers and writers in America who were trying to get it.”
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EDIT: archived a copy of the RS article, just in case :)