The Playboy of the Western World gains its title from the scene in which Christy can't be beaten in play at any of the village sports, hence he becomes the "playboy." The phrase "of the Western World" leads the way into Synge's theme of Irish mythmaking, then still especially noticeable in unsophisticated peasant groups. With the inclusion of this phrase, the myth of the playboy encompasses the whole world. Mythmaking deviates from reality, as is made clear by the stretch of the title: Irish village game championship can't possibly trump an entire world of athletes. Synge isn't discussing a universal theme but rather exposing a particularly Irish theme, that of mythmaking.
The play opened in January of 1907 at Yeats's Irish Literary Theatre to outraged indignation and riots but over the course of the twentieth century has gained ever greater currency among critics. Had Yeats not held a public debate on the concept of artistic freedom, The Playboy may have died an ignoble death. As it happens, though, the play has by later critics been called "the most rich and copious store of character since Shakespeare’’ (P.P. Howe) and a play "riotous with the quick rush of life, a tempest of the passions" (Charles A. Bennett).
These seem to be the reasons that The Playboy of the Western World has current appeal. Whereas original audiences cared about morality and decorous representations of peoples and countries, the increasing and ever increasing reach for realism, ethnic diversity and authentic representations has brought The Playboy into vogue because it was the avant garde and the precursor of what is presently valued and sought after: unveiled realism. Incidentally, one might argue that this unveiled realism, which is the idol of the present milieu, has been carried so far that "realism" is now a fancy in that it is a reality beyond reality and that it carries such clout that it is creating new reality (of questionable benefit) in its wake, which is a divergent reality from the realism that Synge depicted after living with, studying and capturing in three acts the cultural and psychological realities on the Aran Islands, from which he derived The Playboy of the Western World.