What is real impact of Precision Agriculture?
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The hope is that precision agriculture will be the basis for the next Green Revolution. The first Green Revolution started in the late 1950s and picked up steam during the 1960s. These techniques, now 50 to 60 years old, drastically changed farming in many developing countries, and even turned some of those countries from net food importers to net food exporters. The gains from those now dated techniques have plateaued in many places as of late; in some places productivity has even begun declining.

The goals of precision agriculture are to integrate many aspects of the earth and agricultural sciences with late 20th / early 21st century technology (modern direct sensing, remote sensing, internet of things, big data, ...)  so as to identify on a very precise scale exactly which land areas are in need of enhanced irrigation, fertilization, insecticides, herbicides, etc., -- and which areas are just fine as-is. The hopes are that this will reduce the overall need for irrigation, etc., thereby reducing stress on the land, and that this will be largely automated, thereby reducing the workload on farm workers.

These are the aims and hopes. The concepts do appear to be working in highly developed areas. But whether they can work well in the developing world is a bit suspect, let alone whether they can work at all in undeveloped areas of the world.

The bigger problem is that many estimates indicate the Earth's human population will increase by almost thirty per cent in just thirty years (from a bit over 7.5 billion to almost 10 billion) -- and that increase will be happening while the first Green Revolution is plateauing / declining. Something has to be done lest many parts of the world fall into famine. Precision agriculture might be one way address this bigger problem. Or it might not.