Dunno about the other visas, but the H-1B is critical to the US position as science and tech leader. One wonder if Trump and his cronies ever thought about how a country whose high school education is ranked 31st in the world for math managed to continually pushes forward the boundary of scientific and tech progress. Maybe, just maybe, it has something to do with all those foreign smart people that somehow kept coming here.
Lets see. Foreign-born workers account for a fifth of STEM workers with a bachelor's degree and more than half of those with a Ph.D. In a paper released last April, Sari Pekkala Kerr and William Kerr find that immigrants account for about a quarter of U.S. entrepreneurship and innovation. Chinese and Indian ethnic inventors account for 22 percent of U.S. patents in 2018.