Those groups are not emblematic of the startup culture. He's mentioning those races to make the point that the lack of diversity within that culture is so stark

Those groups are not emblematic of the startup culture. He's mentioning those races to make the point that the lack of diversity within that culture is so stark that membership in the set of startup tech employees virtually guarantees membership in the set of white or Asian males. He's not saying they are boring or undesirable because they are Asian or white. If startup employees as a set were more racially/ethnically diverse it might defy that stereotype of uninteresting personalities. Or that might just decouple it from the racial predictability. Eg, in NYC I-Banking is a bit more diverse but still induces that same yawn -- in some people -- when you hear someone say that's the field they work in. PS, I upvoted you bc I believe you're asking the question honestly and not in a trolling way. Your comment was grey when I came to it.