The Beach Boys singer Bruce Johnston is leaving the band after almost six decades. The 83-year-old joined the iconic group’s touring unit in 1965, playing more than 6,000 concerts, but is now stepping away to focus on songwriting. “It’s time for part three of my lengthy musical career!” he told Rolling Stone. “I can write songs forever and wait until you hear what’s coming! As my major talent beyond singing is songwriting, now is the time to get serious again.” He said he was also planning to start doing speaking engagements, adding, “I might even sing ‘Disney Girls’ and ‘I...