I'm not sure about appeal to nature here; biology seems rather centralized in a lot of aspects. An organism may be made of many cells, but each of those cells have a specific function. Kidney cells do not compute, and brain cells do not contract to pump blood. When a cell starts doing whatever is best for it locally, we call that "cancer". Centralized management arises naturally whenever there's a need for efficiency. So while there's a lot of distribution going on, I wouldn't say centralization is unnatural. It seems common enough on many different scales.