seems to be the pressing issue these days.
As essentially all other days.

I am in favour of it. But only if it is properly understood.
To me a country is a living entity.
So thermodynamically speaking:
immigration is like consumption.
and emigration is like excretion.
Not literally, but in terms of energy.

Since all we know, according to itself, is essentially a structure of energy.
Well, if you eat more than you can handle, it is not going to end well.
If you eat less than you should it is not going to end well either.
You need a balanced stream to maintain national homeostasis.
If you eat something you should not have, or need to integrate with,
you will become sick. And it takes some time to overcome that.
And in relativity speaking:
think of one day for the country as one year for you.

If you eat the same food over and over, you will function.
But you will not evolve as fast. As you remain within your structure.
You also risk your immune system by not exercising exposure.

Integration, or the national integration apparatus, is essentially what you do with the imported biomass (immigrants).
If you just accumulate you will grow obese and your infrastructure, your homeostasis will collapse.
If you refuse to accumulate at all you will self-exterminate. Starve yourself to death. Essentially suicide your colony.

So to me, yeah, immigration, or movement of biomass, is absolutely necessary for a society to be alive. Because the society is a homeostatic system. A colony. Like an ant-hill.
Just far more sophisticated, since human components who are in the upper half of human mentality are transhuman enough to surpass that template in sophistication.

Did you know that the Christians were the original Transhumans? (Locally speaking)
(Intellectually formulated and defined in lifestyle – I mean you even have an instruction manual. Quite a thick one.)
I mean the church, the organised religion.
That is why they despised pagans more in the past.
Those wild animals living like animals.

I find it downright hilarious and laughable when Christians are against my Transhuman endeavours. At least the religious ones. Because they do the exact same thing. Does not happen very often in Sweden though. The church is keeping up rather fine with the times here. While they also maintain culture and traditions in the conservative fashion.
This is more where the more rigorous systems are established. But they do the same.
Only not in awareness, and of course more in an alignment suited to their defined goals.