Looking different and having different customs does mean having different psychologies. If anything i believe it’s you who hasnt been working with people of diverse backgrounds, otherwise you’d know personality traits are shared among cultures and ethnicities. Otherwise you’d have a different psychology manual for each nation and ethnicity. The question original question is asking about why some people are beating the bush when discussing topics, not how it’s customary to express disagreement. But even that is shared between cultures and the more you work with people of different backgrounds the more you know its the same.