We don't buy organic for the sake of nutrition...
We buy organic food to avoid the pesticides that evil giants like Monsanto try to foist on us, not because we think they offer better nutrition.
Much like taste, if nutrition is lacking in a fruit or vegetable, regardless of how it's grown, you can likely trace the cause to genetics.
When they started breeding tomatoes that could be picked green and survive cross country transit, that's when we started sacrificing taste and nutrition in the favor of saleability. Now that everyone is using those types of seeds, a vine ripened locally grown tomato no longer tastes as good as the "Jersey Tomatos" I recall from my childhood.