No one is suggesting culture should be ignored. It's pride that's the problem. Did you do something to earn your nationality?

Culture in itself is an important difference that makes people a lot more interesting to each other. But the examples given are not the same kind of difference: Olympic swimmers aren't expressing their culture. They're all, by rule, doing exactly the same thing. That the one from your nation does it the best says nothing about your culture, and there's no rational reason that swimmer or you should feel some sort of pride about that.