See "We Wanted Workers" by economist George Borjas for a more skeptical treatment of this "hundred trillion dollar bill" lying on the sidewalk.
How can you possibly recognize this and still decide that your proposal makes sense, in light of events like the presidency of Donald Trump and Brexit? What we have now is a drop in the bucket compared to unrestricted migration, and it's already quite possibly indirectly causing massive political upheaval that threatens to destabilize the first world.