But currently the data is largely hidden and ignored. This is the best their is right now.
Is it though? This sounds rather conspiratorial. A major part of my last job was literally analyzing U.S. Immigration and it’s effects on our economy positive and negative. There seemed to be a very very very large amount of research on the topic last I checked.
I’m sure the EU member governments are doing the exact same kind of research on their immigration and will come to the same conclusion. That Immigration can pay off massively, but that the payoff is reliant on integration effort and having jobs open for them.
Overall historically all Immigration in the U.S has paid off, sure our economy might have struggled to accept massive population growth sometimes, but in the end that population growth allowed for far greater and faster economic growth.