This is only good if the rest of the world is in a similar state to America. If we were talking about just the West and Japan, sure. "Anybody from India who wants to move here we can make it work". Great, now salaries for software engineers in SV are going to drop in half because there are a ton of developers who can fill jobs here, yet Americans don't want to move to India. (Just using India as an example).

There has to be equilibrium or it's a policy that will drive down worker wages, increase the wealth of the 1%, and leave the United States crowded and poor.