> In practice, it's ludicrous to think that the vast US university system cannot produce employees with whatever skills are in demand, so workers must be imported from countries that have much smaller education complexes.

No, it's ludicrous to think that a vast network of overpriced liberal arts colleges with chronic grade inflation can produce enough high quality engineers and scientists for the largest economy in the world, especially when the majority of its industrial capacity is in high value add manufacturing like aerospace and defense, clean(er) energy, pharmaceuticals, and other specialized fields. The rest of the world takes education a lot more seriously than we do and even though they may not be ranked highly by the US News World Report, the rest of the world's universities easily produce enough talent in their top 3% to leave the bottom 80-90% of US STEM graduates completely jobless, at any salary. Paying someone more after they graduate isn't going to make an 18 year old take their education seriously and the best universities in the world can't help a student body obsessed with everything but their education.

It baffles me to no end that a few H1B immigrants from some podunk mining university in Siberia can bang out a complex PCB on their own faster than the vast majority of MIT/Caltech/Stanford EE graduates I know. Even though the latter have a year+ of internships each under their belt, they're useless without months or years of on the job training. When they do get that training, they're still years behind someone who had no choice but to work 40 hours a week while going to school in a poor country with few prospects. This isn't a hypothetical: I've met and worked with half a dozen different people in SoCal from the same Siberian mining university (because it was one of the few in the Soviet Union without institutional anti-Semitism) who came here shortly after graduating to fill long empty mid-to-senior level engineering positions. None were underpaid or exploited and many filled positions that their employers were actively trying to fill for years.

I'm sure that higher salaries would push a few people in the direction of STEM fields, and a few of those would be capable of filling positions that an immigrant would take. If the salaries went high enough, I bet it might even obviate the need for skilled immigration entirely but Americans as a nation just don't want to pay the price, full stop. It would mean doubling the amount of money we give out in research grants, let alone every other corner of our economy. Just look at a variety of goods in Italy or France: the public is willing to pay more per article of clothing or furniture so there is a large industry of highly paid artisans with job security and high quality of life, willingly supported by consumers.

Disclaimer: the above probably does not apply to a significant portion, if not majority, of annual H1Bs because they go to Tata, Infosys, and other sweatshops. Those are absolutely abuses of the Visa program meant only to depress wages.

Edit to add some more concrete info: based on my parents' old high school/undergrad textbooks and my own experiences, the average American STEM college student spends the first few years of undergrad catching up to the level of a good but not great high school junior in the Soviet Union. Five year dual BS/MS degrees including institute R&D were the norm back then so how do you think the average 23 year old Soviet graduate stacked up to the best 20-anything American? The level of education doesn't even compare.