In Poland pretty much all land owners, anyone of any wealth and intelligentsia were killed either by the Nazis or the Soviets. It's as if the US had a purge 70 years ago and anyone of any means was killed or sent to a labour camp. US still reaps the benefits of both slavery and the past and ongoing discrimination of its minorities - Poland on the other hand does not. First the Partitions of Poland have erased the country from existence for nearly 100 years, then Nazis killed over 2 million people starting with anyone who had anything valuable first, then 50 years of communism made sure than any kind of systematic exploitation based on serfdom was eradicated and burnt to the ground. While it is taught in history books, the entire class of people who might have been perpetuating the practice have simply been killed off or exiled.