Most IT / h1 roles are not based out of the Bay Area [1]. Significant amounts of H1b population goes to doing cookie cutter consulting projects spread across the country and setting a 150k min on the wage means that you won't be able to hire H1s at all in other parts of the country. Obviously this creates a lot of demand for American programmers and personal experience suggests that this will cause a labor shortage.
[1] https://www.myvisajobs.com/Reports/2017-H1B-Visa-Category.as...