Cry me a river. Do you also complain about internal migration towards cities like San Francisco and Boston. It's the same principal at play. Tech workers from all over the US flock to cities where the wealth is. Tech workers from around the world flock to the US because that's where the wealth is. It's not because we like stealing your job.
Developing software is an investment and the people that fund the investment seem to prefer (at least the core of the team) to live nearby. But if you put a hard-stop on immigration. Or if it gets too expensive for people to live nearby, they might just start looking for the talent wherever it is like @dhh.
Bring it on.