The news yesterday of the death of Playboy founder Hugh Hefner did not come as much of a surprise, for he seemed to belong to a bygone era—the age of Marilyn Monroe, to be exact, next to whom he will be laid, to rest. Yet, if you're a charter member of the reading-Playboy-with-a-flashlight generation, Hef's demise should give you pause. In one man's lifetime, "adult" entertainment evolved from pinups to porn streaming, with all of its attendant social, sexual and even demographic dysfunction. No one is judging, of course. But by offering American men a magazine that combined nudie pics and long-form interviews, Hefner put in motion a cultural revolution that has yet to run its course.