There is this theme - even accepted by some Christians - that Christian musicians are second-rate, and that is why they don’t have an impact. But it is a lie. Christian musicians are - quite simply - discriminated against.
Christian pop is usually only known and promoted in Christian circles. Harder-edged Christian rock (i.e. P.O.D., Skillet, Demon Hunter, etc.) has lots of following and appreciation among secular fans as well as Christian fans. Some of those bands are really good musically. I personally find Christian pop to be too feminized, with little appeal to male audiences; you know, the so-called “Jesus is my boyfriend” music. I would rather just listen to Air Supply than most of that stuff.