“Most H1-B visa are IT people”
This has hurt my family members who are IT people. Has driven down salaries and dried up opportunities. Maybe as you say, not in as big of numbers, but Americans are not getting the employment they need and deserve.
The problem with IT workers is that there is a huge surplus of available IT workers in the world. Literally tens of millions of IT workers are looking for jobs.
Why there is such a surplus? Training time!
It takes 7 years to graduate from law school. Then one has to pass the bar exam. My daughter recently finished all that, costing the family $150 in tuition fees alone.
It takes 12 years to become a practicing doctor, including required internship.
It took me 2 degrees (7 years) and 5 years of working in the industry to become a skilled machine design engineer.
IT workers require much less time in training.
My advice to all your relatives is to seek a different field where cheap competition is scarce. What skills I had achieved in my line of work, there was virtually no competition. My employer gave me a big raise everytime I found a better offer.
If these H1-B visa IT workers are stopped, the companies will simply outsource the work. Which eliminates most of the peripheral jobs in the company, such as financial people, building maintenance, real-estate taxes, lower sales by local utilities, etc.