There are 26 million people in the U.S. who have diabetes. There are probably another 10 million or so that have insulin resistance or metabolic syndrome. For these people, bread is NOT absolutely fine; it is a food that should be carefully monitored, the same as all carb-laden foods.
I'm curious how bread is a "remarkably complete food". A typical serving of multigrain bread has the following: 1 gram fat, 110 mg sodium, 11 grams of carbs, 3 grams of protein, 3% of RDA for calcium, and 4% of RDA for iron. Since carbohydrates are not an essential nutrient for humans, that means there's not that much to be gained from eating bread.