Ah, I concede this. Maybe this isn't an issue in US as it is in the UK..
> They are not mutually exclusive: you can do both
What stops industry becoming dependent on it though? There are big advantages to H1B visa workers, there is a risk that it saps market demand. Immigration might be the path of least resistance to solving labor shortage, rather than any long-term native plans.
If technology comes to be seen as a reliable high-paid job, via being sustainably high-paid, then it's reputation will bring in more people. Immigration is a threat to this. You can argue industrial benefit to this, but how sustainable is it? What if the US lost it's attractivity, what would happen to the H1B workers then? The US needs to figure out how to produce workers - being able to skim the cream from other demographics is a benefit, but a dangerous temptation as well.