OTOH there are lots of people who are interested in selling genuine carbon credits. They are pressuring governments to clean up this market. It's a hard coordination problem, since we don't have a unified world government. (Thankfully).
There should be a world standard or standards for genuine carbon credits. Maybe the UN could create an agency that determines such a standard and verifies that carbon credits meet that standard.
It's a hard coordination problem because, like sea shells or glass beads, CO2 is not a good store of capital.