No the main point that Dasgupta wants you to take away from this 6000 word essay is something that he initially obfuscates but ultimately just can't resist bluntly stating. He thinks that citizenship itself is manifestly unfair. To be precise, Dasgupta thinks that citizenship in the West and especially citizenship in the United States is unfair. And he wants to end it, primarily to make people in the Third World wealthier.
The history of the nation state is one of perennial tax innovation, and the next such innovation is transnational: we must build systems to track transnational money flows, and to transfer a portion of them into public channels. Without this, our political infrastructure will continue to become more and more superfluous to actual material life. In the process we must also think more seriously about global redistribution: not aid, which is exceptional, but the systematic transfer of wealth from rich to poor for the improved security of all, as happens in national societies.