I agree that there is some latitude for the difference between a preference and a fetish and that this particular guy may have been misinterpreted, but in general, stating a preference for a certain race means imbuing them with stereotypes rather than allowing for the wide variety of individualism that exist within any particular race. That's the problem with saying, "I like Asians" vs. "I like green eyes" - it doesn't account for individuality and lumps everyone of one race into a pile. Anything that minimizes somebody's individual humanity is objectifying - particularly when there are disempowering stereotypes about their race, such as the one that says that Asian women are submissive and easy to control. Most racism is subconscious and although it might have been more productive to have a conversation with this guy about what he meant rather than to just jump him, it's also important to call attention to potential subconscious bias that has long been normalized in our culture.