And some of those changes were significant positives not only for agricultural productivity, but also for the environment. The biggest of these is the reduced or eliminated tillage... tilling the soil several times a year with heavy machinery was the biggest contributor to soil degradation and even outright soil loss.

First, after tilling, some of the soil literally blows away with the wind. Second, organic residue in freshly tilled soil decomposes rapidly to CO2 and Methane, versus healthy untilled soil where a significant portion of it would decompose to long-term stable humic and vulvic substances... so we have a double negative where we're increasing the global warming contribution and decreasing the capacity of the soil for retaining nutrients.

I've dabbled in farming, and I'm no fan of glyphosate, and certainly not of Monsanto, but I think it's important to point this out because certain knee-jerk reactions, like "ban glyphosate" by themselves are only likely to make things worse. If you ban glyphosate for example, one of two things is likely to happen... 1) it will be replaced by even worse chemicals, or 2) people go back to frequent tilling. There are no quick fixes to industrial agriculture, the only solution is to move toward highly integrated regenerative approaches, and these are by their nature much more complex and labor intensive. It's great that there are more and more people doing that, but big ag keeps them operating at the margins of our food supply.