I never said you're excusing it, but it certainly sounded like you were accusing Poland of being homogenized, as if they were specifically attempting to keep a homogenous population, whereas the reality is that A) they don't have a history of occupying and exploiting people of other races, and B) their transformation into a market economy and subsequent joining of the EU means that their population has generally decreased, especially with regards to young people, and a lack of investment and need to adhere to EU competition rules meaning that it's difficult for Poland to invest in it's own industries and attract immigrants, especially from outside Eastern Europe.
Also we can't forget the huge xenophobia directed at Eastern Europe over the past decade, driven by a combination of anti-Russian feeling, the remnants of anti-Communism, a sort of Western-supremacist anti-Slavic primitivism and a very deep rooted and barely acknowledged anti-semistism.
Obviously you are not doing any of those things at all. I just think that we, in the West, have to be super, super careful when criticising countries like Poland. They're not 'fair game' just because they look white. Poland is a complicated country with complicated socio-political and ethnic identities.
I am stating a fact about the population spread of Poland. I never attributed any sort of intention one way or another. Obviously I'm sure a lot of Polish people don't necessarily want to move to the UK to work construction if they could make a living in their own country.
Your post doesn't seem to address the actual issues in Poland and instead wants to focus on how the issues are okay because they suffered massively previously. I'm not disputing their suffering, and visiting Auschwitz is something that I won't ever forget. However, that doesn't make it okay, and the way their government is going, their attachment to the Catholic Church to the point where it's almost a theocracy, is not something that should be above criticism simply because of their history. Nor is racism just because the country didn't choose to be homogenized.
As a sidenote the last time I went to Katowice, the amount of construction and overall building was startling.