You are missing alternative costs of the fact that more people compete for the same resources, Americans get much lower ROI for their education, it hollows domestic expertise. Companies become dependent on foreign workers. Local jobs pay less, people have less money to pay for products and services.

Short term - shareholders win, long term - everyone loses except the country of origin, where they can bring the knowledge back and develop their economy.

It's like outsourcing, just the foreign workers are onshore.