The art made by Christians today is not only not beautiful, but tends to be among the ugliest art that mankind is producing.
Mark offers a reason:
I think it's the "Little Drummer Boy" effect. Art that sucks (Music=pa rum pa pum pum) is thought to be humble. Art that's good is fancy pants aesthetics that those damn bi-coastal Blue Staters like. So Christians make sucky art and pride themselves on their humility. Til "suck" is decoupled from "humble" the problem will continue.
I'd suggest it's because the Christians making art today tend to be bad artists. In particular, they aren't concerned with whether their art is good, they're concerned with whether it's Christian. And if you can't distinguish between good art and Christian art, you're a bad artist.