> This assumes that we can trustlessly get the CO2 emissions for all countries
Classic blockchain advocacy: it works great provided we solve this unsolved problem of communicating "trustlessly" with the real world!
> you'd have actual enforceable code that can not be gamed
People keep "gaming" smart contracts all the time. Just recently there was a defi attack where someone simply flash-borrowed all the tokens, voted themselves a reward, and returned the tokens.