There are different grades of quality in diatomaceous earth, some are safer, other not so. Is a "fosil stone", so is not unlimited. Diatom skeletons are tiny silica boxes, and breathing silica dust regularly leads to silicose. Would also change the soil structure and increase the damage in the machines needed for harvest.
In the other hand spiders and bats are the perfect insecticide without any bad side effect for plants. Its numbers would increase filling the gap, at least partially.
Organophosphates are well past patentability. You'd be hard pressed to introduce a new one that outperforms the old. They're used because they're off patent and cheap to acquire.
In the other hand spiders and bats are the perfect insecticide without any bad side effect for plants. Its numbers would increase filling the gap, at least partially.