The “lessons” in this article are too simplistic. What is missing is a more thorough examination of the connection between immigration and economic conditions. The article paints a happy picture, one that glosses over and obscures major problems related to excessive immigration in the past. One example: the 1880s and 1890s were decades of great labor strife and rampant exploitation of workers who knew they could be replaced by newly arrived immigrants. There was lots of backlash — the anti-Chinese laws in California for instance. These conditions brought out America at its worst: a population beset with ethnic division, huge disparities in income, and rising intolerance. Even so, the economy back then was rapidly expanding, and expanding in a way that generated new jobs. The tension dissipated over time and reached fairly low levels when immigration levels were reduced.
The article correctly noted the era from 1940–1990 was atypical because immigrants made up a smaller percentage of the population. Interestingly, it was also the era of widespread long-term prosperity leading to rising real wages and to growth of the middle class. With the more recent increase in immigrant percentages has come stagnation in real wages, deteriorating infrastructure, and rising income disparity. I’m not saying there is necessarily a causal effect, but it certainly can’t be ruled out and needs to be studied carefully. Comparisons between counties within a state do not capture the macro effects.
What needs to be asked is whether the current economy can truly absorb the many immigrants allowed legally and illegally under the current system. The advent of AI and robotics along with the mobility of services and manufacturing to overseas locations suggest the number that can be readily absorbed is not all that large.
Further we cannot equate all immigrants in terms of their ability to integrate into the American culture and their willingness to accept American values such as religious tolerance and freedom of speech. Most previous immigrant groups tried hard to assimilate into the society and become Americans. That appears not to be true for some portions of the more recent groups of immigrants. They constitute a historically unique threat to the unity of a country composed of a wide range of religions, creeds, and ethnicities. The combination of identity politics and high levels of immigration could pose challenges to the social fabric never seen before.
All this is not to say that immigration is bad, or to deny the very real benefits the country at large enjoys due to immigration, or to ignore the many contributions that are being made by immigrants to our national well-being. It does say however that the reverse mantra, all immigration at any level is good, is too simplistic and could lead to major economic and social problems if followed uncritically.