It is exactly nationality-based stereotyping, based on a single example.
I did not say Jerry Yang thinks the same way. I said I imagine he could. It's a thought experiment. Can you imagine what kind of life it must be to think that suffering is the mark of success? Open your mind and think about that. What it must be like. How it must affect your kids. How you must have been affected as a kid. Why, what geopolitical factors created that cultural norm? Think. Think. The point of the comment was to think.
And, I would be hard pressed to completely generalize between say China, Taiwan and Japan. While you will find a lot of overtime and overwork in those countries, the way they happen is different and the cultural/social pressure behind that are different. And having worked with Asian Americans (both ABCs and people who came a bit later), I would vehemently disagree that you can easily generalize their behavior solely based on the culture of their country of origin, especially since they have lived in the US, spent time there, gone to school there and will have changed their values and culture over time just from this.
So, I don't think that saying Jerry Yang is taiwanese therefor will overwork his employees is a useful heuristic or likely to be true...
(Aren’t you?)