Immigrants in North America are more successful than the native-born as they make up a disproportionate percentage of the entrepreneurs who drive economic progress and innovation. This has historically been the case despite the inherent disadvantages that one faces by uprooting and starting over in a strange land with little or no assets at all.
By the time they arrived in America, the Jews of Europe were the victims of oppression and forced immigration over many centuries. When they arrived on this side of the ocean they found that the environment was relatively more tolerant to them. Like the Asian, African and Middle Eastern refugees that followed, one of the reasons that their new surroundings allowed them to thrive was because they no longer had to deal with the burdening oppressions that weighed on them. Opportunities increase when you're not being hunted down.
It's like walking around with ankle and wrist weights for most of your life and then having them removed and being issued wings in their place. Superman would have been an average Schmoe on Krypton but becomes a superhero on Earth. This plays out in various other ecosystems. The lowly Zebra Mussel from Russia hitches a ride in the ballast of freighter ships and finds himself in the land of plenty that is the Great Lakes. Those purple flowers that you may see by the side of the road also made the trip over on those ships and now these are considered invasive species because they have been so successful.
Those opposed to immigration often use language that only barely seems to be metaphorically talking about invasive species. Sometimes even invasive species are used for good. The Canadian Wolf was introduced into Yellowstone Park to help bring a balance to that ecosystem. Without a successful predator most of the native species were overeating, overpopulating and threatening the environment. But immigrants don't eat the natives like Wolves do, nor do they consume all the food like the Zebra Mussel leaving none for the locals, nor do they suck up all the marsh water like the Purple Loosestrife, leaving none for the less thirsty vegetation.
A human ecosystem can demonstrate the successful innovation and economic activities of individuals that will leave everyone in the ecosystem better off. This is at the heart of capitalist economic theory. If the proper parameters are in place then the rising tide is supposed to lift all ships. This largely works as long as we don't allow undue exploitation and lose sight of why we want to increase wealth in the first place: To raise the tide for all, not to drown the weak swimmers.