It basically costs nothing and it's a huge advantage for a country to be the dominant sink for international talent migration. Most countries have net brain drain where their smartest people leave... to go to the US. That the US has the opposite problem is really a trivial issue to complain about, and anyone invested in its success should want the imbalance to continue.

And frankly if you're an American high-skilled worker who is concerned about foreign talent "replacing" you (an absurd idea in a labor market where demand continues to outpace supply, and will continue to do so as long as technology advances), then are you actually as highly skilled as you think you are? If you're being outcompeted by foreign talent then you need to "get good" - it's a skill issue.

The argument for foreign workers replacing domestic workers in unskilled jobs makes more sense, because the demand is for commoditized labor and there's negligible difference between employees beyond how little they're willing to be paid. But for high skilled work, by definition, it's your skills that should differentiate you. If they don't, then that's your problem to solve. It shouldn't be up to the rest of society to lower the floor of high-skilled work to accommodate your lack of skill.