This, but OP, I think, pointed to the issue maybe without realizing it:
If you feel you are just a.cog in a capitalist machine and not a citizen of a country, why would you celebrate?
It feels like Fox news and all the wedge issues have done their work and destroyed our sense of collective citizenship. Now the GOP is doing their corporate owners' bidding.
What is the change in the percentage of earth's surface being farmed over that time?
I am skeptical that we are using enough more land to account for this.
Climate and chemicals seem more likely to me, but your idea is interesting if there is data to back it up.