Social media platforms have been blowing up with millions of tweets and posts about BTS, the K-pop band that celebrated their eighth anniversary over the weekend with a live virtual concert called “Muster Sowoozoo.” To discuss the megasuccess of BTS’ virtual concerts, The World’s host Marco Werman speaks to music writer and culture critic Maria Sherman, author of the book, “Larger Than Life: A History Of Boy Bands from New Kids on the Block to BTS.”