We don't have to worry about this one. Since it's still far from the reality. It would be really hard for bitcoin to be the global currency when there are governments who don't like decentralized cryptocurrency. Rather than a global currency, it's more near from reality to be an alternative global currency. Also right now, we're already working to earn bitcoin, and that's already an example of being under by a person who holds more power and bitcoin. Same thing will happen if it will become a global currency. We're still going to work for it just like how fiat circulates.