expected solar driven nitrogen reactor fixation mention cause thats the trinity.
Nitrogen fixation is energy-intensive, so something has to provide energy. Additionally, nitrogen fixation has to happen in anaerobic conditions, oxygen kills the enzymes responsible for nitrogen fixation. In legumes, the oxygen is carried away by hemoglobin (the same one used in "artificial meat"), but engineering these conditions for free-living bacteria is likely going to be problematic.
I'm personally hoping for a catalyst that can work in mild conditions.