I couldn't be bothered to think
Maybe that's your problem ...
Calling for a tollerance in one post and calling names in the next one because you don't agree with someone else's POV.
If you're not privileged, then what have YOU specifically done to "earn" the "superiority" that you claim. This question goes to Krzysztof as well.
I'm not privileged. I was born a citizen of this country and I had to accept the duties this fact carries and the benefits it offers.
Ever heard of heritage? My forefathers built and shaped this country, for hundreds (or even thousands) of years, I inherited that from them, I'm adding my part to the job and some day will leave it to the next generation, that's how it works.
If I had to emigrate (because my life would be unbearable in this country) I would go to a place that would accept me, and I would accept what they expect from me or move on further in search of a place I fit in.
You see Poland had had significant minorities over the ages, we lost them not so long ago, because of WWII (Jews) and the borders shifting after that war (eastern parts of Poland), so we didn't chase them the hell out of Poland (this probably applies only to Germans, but we had reasons, no place to discuss it right now).
People from different countries were living here and they had their privileges (granted by Poland's rulers), they had their religions, customs and traditions, but they were at the same time subject to Polish laws and they didn't try to introduce theirs.
Mixing of the cultures and gen pools is fine as long as it happens spontaneously, two people (from different races, or at least nations) fall in love, they have babies, bring up those children imparting to them the traditions of both cultures (and teaching them to accept the host country's rules). Mutual agreement that's what it should be.
From your posts, however, I got the impression that you would like somehow to "order" race mixing as a rule, it never was and probably never will be.
You say that race mixing was historically beneficial, but why did it happen? Some people were invaded, women raped or people chose to "mix" with the invader to get some privileges, to make their lives better. But the first impulse was to fight, to defend their land. Now that invasions don't happen that often, most countries have some kind of immigration laws to prevent uncontrolled influx of human masses.
Germany, for example, is one of many European Union countries that doesn't allow Poles to work (hence settle, unless you're that reach that you can live in Germany and work somewhere else) there freely (like UK and some smaller countries did). They're doing it to prevent their (economic) heritage, they've worked for what they have and don't want to give it to 2-5 millions Poles that would "invade" their land if the labour market was completely open. I don't see a problem with that. And I don't see Polish people being outraged by the fact that Germans deny us their privileges (because according to your reasoning they are much more privileged than us).