See, that's the kind of thing I've never understood - how could it not be connected? Race has been historically mostly a geographic thing. You'd see Asian people in Asia, African people in Africa, etc. Anyone else had to have immigrated, or is the child of an immigrant however many generations ago. Culture is also very geographic. Immigrants tend to bring their culture with them (which is a good thing!) and parents usually want to raise their children at least partially in their culture.
Eh, I'm not sure what point I was trying to make, and to be clear I don't think your comment was racist.
Culture is obviously correlated with race in some respects. It's when you start talking about the reason behind some of those correlations that you risk (rightly or wrongly) being called a racist.
In another context this statement would be seen as overtly racist.