Well, you may have to read some non-Breitbart-approved sources, but it's out there in the world, overwhelmingly.
One way immigration creates economic growth for us and in other countries:
https://today.ucsd.edu/story/brain-drain-more-like-brain-grain-how-high-skilled-emigration-boosts-global-prosperity
And how our immigrant-unfriendly climate puts us at a disadvantage vs. other developed countries:
https://law.emory.edu/lawyer/issues/2018/spring/features/reverse-brain-drain/index.html
Immigrants keeping us healthy:
https://forumtogether.org/article/the-lifeblood-of-care-immigrants-driving-health-care-forward/