I'm sure there was some racism involved, but Poles were right to be outraged that some American company wanted to take away from them one of the very, very few positive Polish/Slavic characters with a nice story.
I don't know if Americans are oblivious to that, but there are plenty of negative stereotypes for Polish and Slavic people in Europe being reinforced by movies, where they rarely get to be represented in a positive way.
It's really important for these kind of #outrage narratives that all white people are lumped together as one group.