They said the same thing about the Big Bang theory.
Theists have tried for eons to hide their gods. Like the meme states, first it was behind mountains as thunder, later the skies, then the sun and the moon. As knowledge increased it became harder and harder to find hiding places for their gods. With scientific discovery and the Hubble Telescope, the gods are still not to be seen or heard, so now god is hiding behind the Big Bang. There is an easy answer as to why gods are so elusive.