Applying the principle of charity, I personally read this question to be about the definition of the term racist. Does the term racist include prejudice that is based on country of origin? This is a request for a "correct" answer. Because of that, I agree with you. I wouldn't personally flag it as opinion-based.
However, the question is so short that it's hard to know what the asker really wants. I can understand how reasonable people might flag it as a request for opinion. In any case, we're in the dark about what the asker has already considered and why there is still a question. I'd actually flag it to be closed as either unclear or lacks research.