Well I don't agree that modern fruit is "unnaturally" sweet. If anything, the fruits you get in supermarkets today are watery and bland compared to locally grown stuff. Compare a strawberry bought at a farmer's market to one you buy at a grocery store, for instance.

Obviously it's possible to overdo anything, but fruit gives you a whole assortment of fiber and nutrients that you don't get from processed sugar. In moderation it's extremely healthy.