Art made by Christians (music, print, digital etc...) reminds me of Trader Joes. Let me explain.
Trader Joe's essentially sells products that are healthier versions of things we all know and love. This morning I had "Trader O's", a somehow more natural version of Cheerios. They don't taste that great. It's not that they're bad, they just aren't as good as the original.
I think art in Christian circles is a lot like that. It's supposed to be better for you, but often, it doesn't taste, look or sound as good.
I know about a dozen causal reasons, but the observation still stands.