People complain that “Christian” music is/has been behind the times, and just a poor copy of mainstream music. I think that there are some reasons that this perception exists, even though it is not wholly true.
First of all, the majority of people find out about music from what is on the radio. And with there being very little in the way of progressive, rock, alternative, etc. “Christian” music programs or stations, very few people hear the “Christian” music first. In other words, a person listens to mainstream radio, then sometime later hears a “Christian” artist doing something similar and automatically assumes that the mainstream artist whom they heard first, was also doing it first, and that the “Christian” artist was just a cheap imitation.
Another reason is the popular demand factor. For instance, a ska band starts to gain big success. Companies in the music business see a tend and try to jump on board. Suddenly you hear about many other ska bands, whom may or may not have been doing ska before hand. Now a “Christian” ska band, who has been playing ska for years, only becomes known after ska becomes popular. So again people assume that since they have not heard of the band previously, that they must be the copy.
Closely related to the first two reasons is the fact that many people (and everyone to a certain extent) decide what they like based on what they are told by those who are deemed the “authorities”, which can be either a person, a group or an entity. Most often this entity is that of the mainstream media, which includes movies, TV, papers, magazines, and radio. Here again a “Christian” band could be playing ska for ten years, and few people would ever like or pay attention to them. But it is only at the point when the mainstream media says, “Ska is great!” that people will start to listen to the “Christian” band.
Also, Christians who are also musicians, most of whom listen to the mainstream media, will start playing what is popular at the current time. This is the case where “Christian” artist are actually more or less copying what a mainstream group(s) is/are doing. But remember that this is not in any way exclusive to Christian music. This happen just as much in mainstream music as it does in “Christian” music.
I think that more often than not when people are criticizing “Christian” music, it has more to do with a lack a familiarity first, and a general disinterest second. In other words, they don’t really know too much about it, and they don’t really care to know about it, so they come up with some half truths as excuses to for them not to pay any attention to it.
(Note: I’m not sure exactly when I wrote this.)