For anything to thrive for an extended period of time, diversity is necessary. The natural world is built upon this principle but it is also true of thought, culture and art.
In many ways it is the antithesis of monoculture, which by definition is formulaic, stale and incapable of new perspectives.
For creativity to remain healthy it needs to be woven from countless strands of differing ideas. Elements that when taken as a whole, create art that is vibrant, robust and vital.