Well, considering that we'd only be able to feed 4 billion of the current 7 billion people on earth if we turned over like, every possible arable land on Earth to (organic) farming, it's been going pretty well. Even if you just took out GMO and kept all the other efficient farming methods, it'd still be a tough order to feed everyone.
And no, there's two camps to the GMO negatives. One is the people developing/selling them, the other is the actual GM itself. And yes, Monsanto is a dick, though not as bad as some of the worst claims. But for the other, "It's not natural/unsafe/untested/playing-god!", they're both absurd on the face of them (for the unnatural/playing-god bit) and flat-out wrong for the unsafe and untested, since they're like... the most tested god-damn things we have now-adays. 2000 different studies, IIRC the number, on their safety, with no significant numbers of them saying they're bad. (Of course you'll get one or two outlier studies, but the more rigorous ones all agree)
So yeah, making more climate-resistant and more nutrient-rich foods are both excellent, and well-founded (just look at golden rice) implementations of GMO. :v And I GUESS conceptually it can feel like there are other options, since it's such a huge problem, you know, feeding the whole world. But practically, there really isn't the option to NOT use GM.
But average joe-shmo on the street doesn't think in those terms, and all they hear is "Monsanto is evil! GMO is tampering with nature! We're all going to die!" and they think GMO is all evil with no good reason to use it at all. Think it's fucking poison or something, like we're fucking sticking cyanide-producing genes into wheat for the lulz or something.