"People from country X do not generally have knowledge of continent Y because nationally they take an insular approach" is not racism, it's an identification of a root-cause which for anybody that lives in Poland, is quite well known.
So basically, you're saying it's not racist if it's true? Still seems like a double standard to generalize your manager's nationality while calling his generalization of another nationality racist. Especially when you're kind of describing your manager's "racist" pointer to hold true in this context.
