I found a link to the article I found about immigration and the article you gave us about inequality, liberty, and the pursuit of mobility. Both articles talk about immigration, one uses it as a starting point, the other one uses it as the main point to explain the reasons why Chinese immigrate to the United States. The common point in both articles is the United States is a land of abundant opportunities and freedom which mention in the article as " you can be anything you want." America is a free country but at some point, this freedom seems too much and miss out equality yet nothing is completely fair to everyone.

Based on my limited understanding of the article, more inequality brings less mobility for those high-income countries and it's opposite for those low-income countries. If the inequality can not be changed for now then make choices wisely before immigrate. If you can't change your current life it's ok because you already survived. I can't think of other solution for this problem than making a change for it.

I don't agree with those people who immigrate took the opportunities of local people because the compete is equal. If the company hire a person who immigrates here but not you. It doesn’t mean that person take your chance but you are not good as him. The mobility of immigration is huge between China and America not only because of we go to your country but also you come to my country for the attractive culture and history. I see this as a trade just like trading money and one of these two countries will be the biggest winner which won't need to mention because we can see that China's GDP is going upward unexpected quickly for me. I think the immigration trade is one of the reason raises our GDP because the money exchange rate between our countries is different which means Americans pay less to consume in China. For example, both Chinese and Americans have a hundred RMB and dollars. The Chinese need to pay thirty-five RMB for twenty apples but Americans only need to five dollars for them. It is a benefit for Americans. ( I know apples are not that expensive Bicknell.)

This brings to the original point, inequality. Martin Luther King's amazing speech brings freedom to the United States. I think the article is hoping people can stand up for their equality of job opportunities, liberty, and all just like what MLK did. However, this generation is different which also hint in the same article by pointing out the difference between the growth of new business and the old business steady. People are getting lazy and fragile, a people is defeated only by one failure. Did MLK give his speech easily in that generation? Using my partial understating of US national conditions, maybe Obama is the one who fed the pigs. Although his original intention was good.
Nothing can be changed in the past, Donald Trump is the president of the United States. At least he almost his life on money and still is, maybe, let's expect his action of saving this great country by starting to build the wall. (Did it really fell?)
https://www.pri.org/stories/2012-12-21/why-chinese-immigrants-choose-america