Transience is the very essence of the entertainment business, unpredictability its warp and weft. Early this month, the market research and data analytics firm YouGov published the results of a startling poll. According to interviews with 1,254 adult Americans, 30 percent of millennials have no best friends, 27 percent have no close friends and 22 percent have no friends at all. Not surprisingly, the report named them “the loneliest generation.” But loneliness is all around and perhaps nowhere more profoundly than in Hollywood. Here’s what surprised me: that the statistics weren’t worse, for older people as well as millennials. Look...