You'd think this would be apparent to farmers, who work with plants, animals, and nature all their lives.
There must be a psychological defense mechanism at play.
If their entire livelihood depends on GMO farming, and there is such a strong pressure to confirm to local standards in rural communities - it may be literally impossible for most farmers' brains to consider the other side of the issue. There is too much for them to lose if they find out they are wrong.
It's the same thing I see when trying to wake up many suburban babyboomers to the idea that they were blind tools for the last 60 years, fulfilling the desires of the cultural/political machine, and giving up America's freedoms, in exchange for a high standard of living and easy credit to buy material things.
Their brains simply cannot afford to consider it as a possibility, and they are already satisfied enough, enjoying their nice houses, retirements, and stock accounts - feeling like they won the game of life and are no longer obligated to put forth any more effort or make any lifestyle changes.