Yes, for the US, it’s nearly 90 % built by immigrants, but that’s around 100 – 200 years ago. So the most current generations are natives in the way, that they were born in the USA. There may be one of the other from around 192x. What we also know, the US has been a land of immigration since ever and that’s true nowadays too. It’s a bit different in European countries. One can say the „native“ population is a bit older.
In Germany in the 50-ies the immigrants were probably not supposed to stay, they get the name „Gastarbeiter“, so guest workers. But they surely have built Germany as well. And there are tons of immigrants to Germany which just stayed, here married and got their children. So what are they now? Immigrants or not? Can we agree that to be an native, you have to be at least born in a country, but wait how about you stay there for decades and get the citizenship. Is that a good measure?

I don’t think so, to be a native, you probably have to speak the language fluently and most likely have stayed most of your live in some country, but let’s be honest you will be the „stranger“. So it’s absolutely not clear when you become a native and stop being an immigrant. But let’s take as a base line 30 – 50 years. Is that acceptable?

So if we take that as a base, one can say nowadays most countries are built by natives. But immigration still play a major role in nearly every country. At least those of the European style.

What we should agree upon is that immigration is a fact in nearly every country on this earth. What we probably should insist on, that you at least speak the language fluently. If that’s not the case, you are not a „native“ – sorry.

I tried to immigrate to the US and again for now two years I didn’t get the green card and to be honest, that sucks terrible badly.