Technology believers believe that bitcoin is the mission of decentralization, the future of the world currency.
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In the world of BTC, new centralization has begun...
This is a very interesting point. I mean, it never occurred to me. And you are probably right in this respect.
However, this doesn't mean Bitcoin cannot be a global currency because, in fact, it already is in some way. It is still evolving so we'd better wait and see what it's going to be in the end.