I agree with parts of your stuff.. here's an argument I might make which on some level overlaps.
A Nation state is not just a birth lottery number. My parents did not conceive me, and then throw a dart at a globe to determine my life.
A nation state is fundamentally a tribe. My nation state has a culture, a group of people which raised and shaped me.
As such, immigration should be controlled based on whatever factors a society rationally decides on. If we need more labor, we get more. If we have the benefits to extend welfare outside our tribe, we do it.
The birth lottery argument is one you get to make when your society is peaceful and prosperous. If your life is at stake, your nation reverts to being what it began as, the reason we evolved to form and attach ourselves to groups: a mechanism of defense and collective protection.
And my nation has evolved as a culture. There are things I won't let into it. If you believe in murdering people for being gay, I don't care if your children are likely to be more moderate than you are. I don't think you have a place in my tribe. And I don't know if we can screen for that. And I would never want to just say "Muslims can't immigrate here," simply because their society often behaves in that way.
But, if you're talking about unselectively opening the borders to millions of Muslim people, for example, you aren't just letting in individual people who will interact with our culture and change. You're talking about letting in a not-insignifcant fraction of a society, which will on some level become a tribe within a tribe.
It's such a paradox to say research shows immigrants perfectly assimilate in one breath, and then that the us was shaped by being a culture of immigrants. Frankly, it seems like there's a vast sociological difference between people who opt to move somewhere, and mass migrations such as the Hispanic immigration to the U.S. or even the refugee asylum in Europe. It's known that immigrants living together assimilate far less, which happens much more with mass migration.
That is not to say they are bad, but, it's frankly completely fucking stupid to act like they don't result in cultural shifts. More than 10% of Americans speak Spanish at home! And I think that's awesome, but if I wanted to be a restaurant manager, I probably couldn't even get hired without speaking Spanish.
However, evidence has suggested that immigration above all else vitalizes to the economy and is very very neutral or positive on even blue collar workers.
So on balance, here's my personal issue with the neoliberal paradigm:
People outside of my country are not the same as me. In a vacuum they are equally worthy of everything good in life, but the people in a society have a responsibility to prioritize each other. It is literally the reason societies exist.
It's known that very open immigration is overwhelmingly mostly beneficial to society.
So a lot of people in this sub say- my country should accept more immigrants. Let's open up our borders some more. That's pretty clear for me too.
But somewhere that fell into 'lets have open borders. Completely. End of discussion.'
But frankly if I'm German, I want my country to discuss for a minute accepting nearly 1 million Muslims. I might not want so many people coming-out from cultures largely diametrically opposed to my own. I would want to discuss other solutions to the refugee crisis- such as establishing camps and lending aid closer to the middle East. And that conversation would also lead to better integration policies- what are our specific qualms, and what needs to be addressed before we are willing to open our society?
To think that is not even a valid conversation to have, as a nation, as a culture; that nations are just completely fake lines with no identity, national priorities or agency for their own citizens, is completely over the top.
If you think free movement is a liberal right, and borders shouldn't exist, ask yourself, how would you feel if the world was fighting for fresh water, and there wasn't enough for anyone except the people in your country and maybe one more. Who gets the water?
If you say "we all share" you're 1. Lying and 2. Suppressing your own evolution. Our groups evolves with us. They are genuine, and concern for them is genuine. Accepting this fact is not the same as giving in to irrational, childish xenophobia. It's just who we are.