Very true, but I think that blockchains will only work for the good of society if we the people make them work. As this article on Scientific American demonstrates, if the blockchains we end up using as a society end up being owned by the same private entities we have today, then we are more fucked than before. Imagine if Facebook ends up still being popular, but it runs on a private blockchain. That means that now our data would be completely indestructable, but under their control. The blockchain by itself won't do the trick, I think. Its the Blockchain + Us that does it. Even today with cryptocurrencies, we see some blockchain based cryptos becoming centralised, some would argue bitcoin is in danger of such. So I think the nanny days are over, when society sits back and expects the 'authorities' to do whats best for us. It won't suck itself. We have to come together as humanity and employ these new techs for common good, me thinks. The good thing is, FINALLY we have the technologies that enable this to happen, but we still have to keep an eye out.