Two billion is a crazy population prediction even if open borders was enacted. Relative quality of life would decline very quickly with open borders, and the immigration level would slow down dramatically.
I also read some estimate that "only" 500 Million people world wide want to immigrate to the US. Overall I expect the quality-of-life gap between USA and the 3rd world to continue declining over the next couple decades.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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