More knowledge means more neural connectivity, which means a greater level of creativity (as long as you also develop critical thought at the same pace.)

For art, you need creativity. People tell artists that "the best way to paint/write/draw/act/sculpt better is to go out and experience the world." Well, in the same way a degree in the sciences offers a good topical coverage of the knowledge the world has to offer, a liberal arts degree offers a pretty good topical coverage of the experiences the world has to offer, so you can decide what to dig into. They're useful from that perspective.