If Catholic Latin America hadn’t been making so many babies over the past few years, the Pope wouldn’t be demanding the U.S. with our 300 million population open our borders to let in all 600 million of the Latin Americans Catholics.
This assertion is exactly wrong.
As of now (2019) at least 5 Latin American countries now have fertility rates below the replacement level.
If you'd like a more fact-based hypothesis look into the dismantling of Mexico's and Central America's rural economies by NAFTA, destroying small farms and communities to impose large export-centered agribusiness (think corn--> ethanol. ) Rural Mexico and Central America are being emptied out -- everyone pushed out of the pueblos and into the big cities (e.g. Mexico City) and unemployment and displacement misery.
To seriously oversimplify, blame NAFTA, blame international banking, blame the Bush family.
Conversely, if Protestant Americans had been making babies, then maybe we could keep our entitlement programs funded without hoping that a bunch of illegal immigrants would solve the problem for us.
It would be interesting to know how many are Catholics in name only, are C&E (Christmas & Easter) Catholics or were only baptized Catholic.