Yes the idea is perfectly sensible, the issue is that such schemes are probably a practical impossibility for humans to implement and police in a such a way tha

Yes the idea is perfectly sensible, the issue is that such schemes are probably a practical impossibility for humans to implement and police in a such a way that we achieve the goals or reducing co2 output, rather than just achieving a way for people to game the system for profit. Even if everyone involved operated with good faith, even accounting accurately for the co2 externalities accurately is very difficult, and you can be sure a huge percentage of people will not be acting in good faith.