Global mining is concentrated in the hands of a few. The maintenance and development of bitcoin is concentrated in the hands of few digital farmers. The influence of virtual currency is concentrated in the hands of a few big v.
They are the new army, the new bureaucracy, the new emperor. Are these people trustworthy?
The emergence of BTC is a technological advance in the history of human currency. It makes up for the deficiency of the existing monetary system and should also promote the reform of the existing monetary system.
IMO, Bitcoin cannot become the future global currency because of its consensus mechanism, Proof of Work.
Despite if the current state of POW mining is concentrated or otherwise, it is too easy for any one of G20 to convert nuclear power into electricity and destroy the whole POW network. Moreover, G20 can be
incentivised just to protect the value and liquidity of their fiat currency.
In this case, POS seems to be more secured when it comes to protecting the network from G20 attack.