This is what I think is the difference, In Japan and China there is no melting pot of culture,
On the contrary. The Chinese have over 56 separate ethnic groups. However, they see themselves as all Chinese, the same as in the USA.
they have a system where everyone has a role and knows what that role is. The religion, school, social life, it’s pre determined.
That was called "the class system". The advantage was that those who weren't really sure what to do, and/or weren't that self-motivated, had some kind of idea of what to do so they could have a job, a home, friends, a relationship and maybe kids.
In USA all the cultures create diversity, and schools and many jobs encourage you to adapt to diversity.
The class system was dropped in favour of equal rights, on the basis that some people were given roles that most of them would never be happy with, and so the class system was corrupt.
The current system was that everyone would have the opportunity to go for almost any job, as long as they applied, and jumped through the necessary hoops to rise to the top.
A lot of people are unhappy with the new system, because now each person's results depended on how self-motivated and how self-ish they were. So those who weren't really sure what to do, and/or weren't that self-motivated, had no idea of what to do so they could have a job, a home, friends, a relationship and maybe kids, and many of them became highly unproductive, and ended up on benefits.
It’s mostly Christian conservatives that do not like diversity I think.
Ironic, because Xianity is not that popular in Japan and China.
Also ironic, because the attitude of Westerners to value equal rights was taken from things like fair rents that were established in the Courts of the Chancery, who were priests, and who took the idea of fairness directly from the Bible.
It would have been better if we have not "thrown out the baby with the bathwater", so to speak.
E.G. If we had kept the security of the class system, and simply made it more flexible.
E.G. If we had made it select for competencies and not things like one's race, gender, sexual orientation, etc.
But alas, we didn't get that. So we ended up with a system that allowed anyone to go for anything they wanted. They just had to go for it.
That was better for those who had bags of motivation, such as the children of the wealthy, who are trained to win lots of competitions since birth. So they became even more wealthy. Economic inequality has risen consistently since the 1950s.
It was much worse for those who had a lot of ability to help the world but weren't that selfish and so would have been likely to want to help the world, but not themselves that much. So less problem-solvers and so the big problems of society got bigger and bigger.
But even in government they require everyone to take diversity classes every year to encourage people getting along.
I've never heard anyone suggest that people in government are easier to get on with than most people. So it would sound as if diversity classes are failing to do anything positive.
Are you sure that's the purpose of diversity classes?