I don't think any coin will have a significant impact on society until a very substantial percentage of the population have access to it. As such efforts like Steem to give people access to currency a) for free and b) without needing a bank are very important. I'm looking at other efforts like BAT and the Brave browser that will further expand the scope of the consumers (readers) and publishers (writers - even if we are only publishing our comments and up/down opinions) among us. If those earnings can then easily be converted to other currency via bank-free distributed exchanges and traded for other goods and services we are well on to our way. At that point things like Grant coin and many others will have a much greater impact.
Anyway, blockchains aside - your post has some very interesting information about Iceland. It's amazing to think they have a population of just 300,000 - that's less than the city I live in and it's not even a big city. They have a small population but big dreams and that's encouraging. If they can do it then why can't almost every city and certainly every State in the USA? Why do we even need a Federal Government? My theory is that it only exists now to keep the States in compliance with the Federal Reserve banking system cartel. I'd love to see one of our smaller states just do away with private banks printing money and only have a State Reserve fund like Norway has a Sovereign wealth fund worth well over $100K for every man, woman and child in that country. And they didn't even start it that long ago relatively speaking. Imagine if the US had done that with our oil resources from the start. We could all be living like kings and quite literally the most envied country in the world - assuming we did away with the rent seekers in the middle of every transaction.
Sadly even with another 30 or 40 years I don't think I'll live long enough to see that happen in the US, but it could - one might even posit that "it will" since the technology, like public key encryption, is out of the bag and you can't put it back.
What can I say - we live in interesting times!