There is one important difference. Chinese and Japanese never exploited black people, while some white people enslaved them, committed genocides against them, devastate their countries, manipulate them in ways that left scars for generations etc. While on the other hand, Chinese and Japs absolutely have no reason feel black guilt and are more relaxed.
I never enslaved or killed anyone. Why should I feel guilt? Do all black people collectively feel guilt over the khoisan and pygmy genocides due to Bantu expansion in Africa? Do they all collectively feel guilt over the continued slavery and racism against the few pygmies still left alive in the Congo? After all, it's being perpetrated by "black" people. The idea that because someone is the same skin color as me I am automatically responsible for their actions is...kind of racist? I'm not part of some Borg "white" hive-mind collective, sorry.
Japanese people also tend to whitewash their actions in WW2, focusing mostly on how they were poor victims of the first nuclear weapons. Do you think they feel any less relaxed about the virrulent racism they continue to hold against chinese people to this day, and vice-versa, despite a very recent war that claimed millions of innocent civilians, backed by a sense of racial superiority? Ethnic cleansings and rivalries were the norm throughout most of human history, anyone who has even a cursory knowledge of the history of civilizations and war knows this. And it continues to be the norm for most of the world population.
Multiculturalism, secularism and the ideology behind it is entirely and uniquely "western", linked to enlightenement era values that we used to give lip service to instead of actually following. The idea that we hold ourselves to this higher standard while forgiving other, "less powerful" ethnicties for the same crimes reeks of White Man's Burden. As if "white" people really are so powerful and dominant that a change in their ethnic identities will be enough to eradicate racism and prejudice worldwide.