But have you noticed, the increase in yields is also associat6ed with a lowering of oil and protein content. There are no free lunches.
I’m no longer close enough to farming to know the protein content etc.
However, corn is now bred for specific uses, feed, ethanol, plastics, whatever, and can then be matched to it's end use.
I'm reasonably certain that protein content for corn bred for animal feed has a higher content now than even 10 years ago, thanks to genetic modification.
For example, a recent magazine had a comparison chart on which hybrids have the better production for ethanol under varying conditions, including the shorter growing seasons, which may be caused by general atmospheric cooling.
While there is no such thing as a free lunch, we are still in the position of only exploiting a fraction of our seed potential.
Think of seed production as in the computer stage where the 286 CPU is the latest and greatest. We've only scratched the yield potentials, and future production is more likely than not to exceed even our wildest imaginations today.