I was in the fertilizer business for twenty plus years. I went from Roundup's original introduction in the seventies to the beginnings of Roundup Ready seed. I kept a book in my office (as an EPA requirement) that allowed any employee or customer to view the safety of each chemical.
Roundup was way safer to humans than the cocktail of other herbicides that it replaced. It felt like considerable progress at the time although we all knew it would lead to Roundup resistant weeds in time.
From the beginning there was a small but loud opposition to GMO seeds. Some scientist, usually in Europe, would produce a report that Roundup causes cancer or such. Six different Midwestern universities would try to duplicate the research, fail and then publish exactly where the original researcher made a mistake.
I don't claim to be a scientist but as an interested observer I think that's how the scientific process should work. Now they've switched battlefields to the courts and gained several early victories. I predict they will be overturned on appeal.
I agree with you on monocultural crops. I think rotation should be encouraged but I'm not exactly sure how to do it. What I don't want to see is the government telling farmers what they can plant. They could provide financial incentives however if they can convince the taxpayers it's worth the price.