The problem in the US, as I understood it, is that there is shortage of workers in IT [1]. To me, it sounds like turning off the stream of potential workers, without fixing the underlying issue. With the current rules (85k H-1Bs a year), it would take 10 years for immigrants to fill all the spots. There may be a lot of untapped talent left in the US (based on under-representation of women, that's a discussion for another time), but somehow, the vacancies are not getting filled - what gives?
In addition, it seems that even currently, H-1B program has rules to make sure the wages paid are fair [2] - if they are not, it sounds like a problem with enforcement, or with how prevailing wages are calculated. To me, based on [3], it does not look like calculating the prevailing wage is the problem.
[1] "In the past three months, U.S. employers had about 918,000 unfilled IT jobs, according to IT trade group CompTIA." - https://www.wsj.com/articles/americas-got-talent-just-not-en...
[2] "Employers must attest to the Department of Labor that they will pay wages to the H-1B nonimmigrant workers that are at least equal to the actual wage paid by the employer to other workers with similar experience and qualifications for the job in question, or the prevailing wage for the occupation in the area of intended employment – whichever is greater." - https://www.dol.gov/agencies/whd/immigration/h1b
[3] https://www.flcdatacenter.com/OesQuickResults.aspx?code=15-1...