Let's assume this is true. There are many simpler and smaller-scale coordination games out there. Why hasn't any of these adapted blockchain?

It is quite a stretch to think that you can go from 0 adaptability to 100% adaptability in one of the largest scale coordination games imaginable (tracking carbon consumption).

For example if you told me in 2002 that one day most of the world would be on Facebook I would have been very skeptical, if then you showed me all of Harvard using it like crazy, my scepticism would have decreased significantly.

It is the lack of successful use cases even at smaller scale that I think preventing many people believing in the grand vision.