Fiber is at the heart of digestibilty in bread and lots of other food. Wheat-wise, the fiber's in the bran, which gets removed during milling then added back for whole wheat flour. Therefore any fiber/digestability difference would be between bread made from whole wheat flour and bread made from enriched white flour.

On the nutrient side, it's guesswork for now. I'll be very surprised if there are any nutritive differences between unsprouted and sprouted whole wheat. If such differences do exist, I think they might favor unsprouted because sprouting takes some energy. While the plant's growing, that energy would come from soil nutrients and the sun, but after harvest it would come from the nutrients in the germ. That's my guess.

I don't think the difference is big. I found something that compared "unintentionally" sprouted wheat to unsprouted by way of evaluating sprouted as cattle feed. I recall it saying that sprouted wheat cattle feed is slightly less nutritious than unsprouted, but that the difference was immaterial. (My guess is that the slight difference was because of the energy issue I just mentioned, but it's only a guess.) In any case, I return to the point I've made a few times: If you grind a wheat kernel into a fine powder (a/k/a "flour"), how could the growth of a stub off of that kernel that had no source of nutrients while the stub grew ADD nutrients? Where did those extra nutrients come from?

The argument from the sprouted wheat believers is that the nutrients in the sprout are more available than the nutrients in the berry. Maybe so, but I've yet to see the evidence, and at the very least the logic is open to challenge.