In this case, the problem is that there's a huge difference between public perception and reality. For instance, you talk about herbicides: A modern GMO actually lets you use LESS herbicides and insecticides, and often far less dangerous ones than many that are OK for labeled organic crops, and happen to be far more toxic.

As far as updates on the field producing toxins, GMOs are actually more controlled, genetically speaking, than something that doesn't come from big agribusiness. I can irradiate my seeds to create mutations to use then on traditional breeding, and call myself organic afterwards!

As far as growing well in an area or not, that's why there is testing. Selling a seed that yields poorly to a region would lead to a major economic damage to whichever company is selling those seeds, so everything we can find at a seed store from a major manufacturer, whether GMO or not, will have more than enough agronomic information to make a farmer's decision easy. And besides, I don't know how many farmers you've talked to, but they tend to be a pretty conservative bunch, as far as making sure that they don't bet a lot of hectares on tech that they haven't tested first in a smaller part of their fields, and only plant everywhere if they expect a significant profit. When yields are already very good, and grain is cheap, expensive seeds just sell less across the board.

You don't get much opposition to GMOs among farmers: they just go with what is more profitable for them. Same thing for industrial companies that use the GMOs products to feed cattle or make biodiesel. It all comes down to people that are afraid of what they don't understand, and just choose to be afraid in ways that work well with their political affiliations.

If we were REALLY afraid of food being dangerous, and with untested genetics, we'd actually ban the organics, because there's a lot more genetic variation that is unaccounted for in traditional farming products than in something that comes from agribusiness.