Banana hit the nail on the head. Not only has wheat become a gluten dense product in the last 60 years but the processing has changed to separate out the bran and germ from the endosperm. The result of this newer method of processing is that the resulting wheat product causes massive spikes in blood glucose levels in the consumer. Additionally the way we actually handle wheat has changed as well. People used to soak, sprout, and ferment grains prior to turning them into say bread for example. These processes actually increase the availability of the nutrients like amino acids while inhibiting enzymes that would otherwise prevent uptake of the nutrients contained in the wheat. It's all just more of the same fast food culture where an inferior product to market quick is better than a superior product to market later.
When you add to this the fact the strain of wheat itself is a dwarf meant to maximize yield at any cost you get Zinc, Copper, Iron, Selenium, and Magnesium levels up to 30% lower than in varieties like Emmer, Einkorn, or Kamut. In case anyone is interested in the mechanism behind things like celiac or gluten sensitivity it is essentially that the person's immune system is turned against them by the incoming proteins. There have been studies that have taken celiac patients and given them Einkorn based wheat products with no ill effects so it seems as though it may not just be the amount of gluten in the dwarf wheat but also the break down of proteins and possibly their arrangement.