If this biohack is so good... moreso if it happened to be simply viable in nature - then why didn't it evolve and persist already ?

I can see how a simple notion of helping carbon capture could feel reassuring, but the true motivation behind this is the commercialization of a partially understood biohack which cannot be recalled once it is mass propagated into the system of time-served species on this planet. Time served in Epochs. Billions of years of development which somehow managed to perpetuate fertile habitats with a diversity of species and inter-relations, which to this day goes beyond comprehension and over all of our heads...