Let's say you want to minimize atmospheric CO2. If only because it appears to impair human cognition, perhaps permanently and globally within 300 years if the current trends continue (based off me estimating ~2PPM/year increase from current levels and the 1000PPM cutoff in the article – the linear-ish fit is meant only as a general guess, but a reasonable one).

The problem is, the best way for us to capture CO2 is (perhaps) with trees. I can't find any other, more promising carbon-offsetting options. That doesn't sound like a problem until you realize that the CO2 isn't exiting the carbon cycle, it's just being delayed there. The tree will decompose eventually, and the CO2 will re-enter the air.

Unless it doesn't decompose, or it decomposes in such a way that the products of that decomposition don't re-enter the atmosphere.

Of course, we could use cyanobacteria and let sediment form from their blooms, which is (I believe) the thing that actually sequestered almost all of the CO2 that would otherwise be in our atmosphere. But it's not entirely clear to me how to build cyanobacteria megastructures, or why their waste is better sediment that trees.

If you can just turn landfills into giant (charged!) batteries of natural gas, this seems like it would help. If nothing else, it would make natural gas easier to get at when we need it.