The obvious limitation is that conventional agriculture can't scale endlessly. This isn't controversial, even among conventional farmers. It's a known issue that the 'next green revolution' is needed to feed the ever expanding billions of people on the planet. Conventional agriculture, while a modern miracle in many ways, is just inefficient – in space, resources, etc.
One also can't just hand-wave over the negative externalities of modern farming. Pesticides, soil-carbon loss, and the energy requirements are completely unsustainable.
It is true that there's an enormous difference between a 'food forest' and a natural one. A lot of the research suggests that to adequately address climate change, we can't simply convert farmland to food-forests and call it a day. We actually need to return a significant portion of land back into natural forests.
That is the exact opposite of the truth - conventional agriculture is conventional because it scales so well that rural unemployment is a massive problem and that picking up the end product is in many cases the biggest economic problem.
There are problems but to deny the merits is delusional and dooms failure any insane strategy where a small shepard and veteran slinger believes himself the strongest and tries to wrestle Goliath instead of just slinging a rock at his head.
I stand by what I said. It has worked. Has. It will not scale indefinitely. This is not a controversial statement. This is precisely the motivation behind genetic modification and continued research. It is why conventional agriculture talks about looking for the next green revolution.
One also can't just hand-wave over the negative externalities of modern farming. Pesticides, soil-carbon loss, and the energy requirements are completely unsustainable.
It is true that there's an enormous difference between a 'food forest' and a natural one. A lot of the research suggests that to adequately address climate change, we can't simply convert farmland to food-forests and call it a day. We actually need to return a significant portion of land back into natural forests.
1: http://carbonfarmingsolution.com