This isn't really news.
We use nematodes as organic grub control where I live, there's a pesticide ban.
Organic fertilizers are just a food source for micro-organisms / nematodes, the micro-organisms turn the organic matter into chelated nutrients which plants can absorb and consume. Nematodes are the kings of soil, on the microscopic level.
There's millions of different types of nematodes, each with specific purposes. They make up 80% of the life on earth. New ones must be discovered daily.
All weeds evolved to serve their purpose too, they exist to help, aerate the soil, draw nutrients from deeper down, keep it from drying out, attracting beneficial insects, providing shade etc. They take root and thrive in areas that meet their specific requirements.
Soil biology is interesting.