Silicon Valley already figured out that if you recruit "the best minds" from other countries, those countries have a much harder time building domestic competitors
so from an evil standpoint, the US immigration system doesn't make any sense -- because it's another extraction market to exploit.
h1b visas allow you to work your employees under terrible conditions for less pay than their peers, sure, but the whole 'oh well, we don't want you to STAY here' thing isn't evil enough if you're going full capitalism. it's just cruel. full capitalism would make it real easy to get here because you're removing competitors, even if that means being slightly less cruel