I think bitcoin could rise up as sort of a natural default one world currency for sure. I hope it actually happens as a truly borderless universal currency would be amazing in my opinion.
Impossible. Bitcoin is not decentralized and no crypto-currency can be entirely decentralized. A single, borderless universal currency would NOT be amazing in a good way, rather it would be slavery because it will always be controlled by those who have the most (political) power.
I disagree with you but I think you're just being semantic on the issue of decentralization. Can you give me an example of a currency that is indeed decentralized if you think bitcoin or any crypto isn't? I also don't get how bitcoin can be controlled by those with political power. Seems pretty free from that at the momemt.