The emergence of the visionary and provocative television of the 1990s and 2000s, the period that gave us The Sopranos, The Wire, and The Larry Sanders Show, owed a great deal to HBO, whose narrowcast distribution model and welcome appetite for risk helped make such programming possible. More recently, the premium network has found distinction with Show Me A Hero, True Detective, and Chernobyl. Sex Diaries, however, HBO’s new series of 30-minute documentaries about the sex lives of Brooklyn hipsters on the make, is a much more cynical enterprise.