I read a book, about world agriculture. And it is fascinating. (I consider it poorly written or translated. I read a book about writing before, and it looks like the agriculture book is overflowing with examples of bad writing as overusing passive voice or verb be.)
The book describes how agriculture developed from slash-and-burn to modern and synthetic. It counts how many people land can support depending on the techniques and development. The authors go through various parts of history. They deal with Egypt, Rome, and Middle-Age Europe.
In the end, the authors offer a bleak picture of the world. The agricultural production is unequal and highly skewed towards developed countries. These countries invested in the production and now can churn relatively cheap products despite higher wages. (Farmers are 1000x more productive with modern equipment and investments)
The problem is worsened by the policy of developed countries to subsidy agriculture. So products from developing countries cannot compete.
The problem with effectivity does not have a clear cut solution. Lowering agricultural prices destroys poor farmers. They cannot innovate (and this wreaks the economy because agriculture is a large part of it in developing countries). Increasing the prices helps poor farmers to innovate and get to equal footing with their more developed counterparts, but it would mean starving others to death.
I prepared some visualizations, that illustrate the point. The data are from here. Netherlands should catch your attention. It is a country that exports a lot. It is the most agriculturally developed country.
This is a link with nice graphs about a similar topic.