Partly you are right. If you know China's history, you will know that China is good at making other cultures their own because Confucianism or Taoism were very powerful in Acient China. And they are also rooted in every Chinese person's heart, even in modern society. It is just like in India, young people still live with their parents after they get married. it is the same reason.
And i keep my doubt that India is good at dealing with too much diversity since there are so many terrorists and argue in India. God bless India.