This is true too.I think it is mostly differences in our bodies. If it were differences in the wheat then more people would be able to eat the types of wheat that have not been modified (gmo or selection).
We have done an awful lot of messing with our bodies: drastic changes in what we consider food, how much and what type of sleep we get, what sorts of substances we are in contact with, many more areas.
In my case, I'm inclined to think it's mostly due to the change in the grains. Probably a mix of both, though.
We're going to be paying for this, likely for decades. We're paying for it already, but it will keep snowballing. As I have said several times, I'm glad I'm not 30.