The Trump administration should consider voiding all existing H1-B visas, without exception, and enforcing that all holders return to their home countries, before being eligible to re-obtain a H1-B under new, fairer rules. I know more than a handful of very qualified 40+ folk who were laid off over the last couple of years, and told quite frankly, and with no words being minced, that they were too expensive for the company, so their jobs were being "out-sourced" to cheaper/younger workers.

Most H1-B holders are from pretty desperate circumstances and put up with just about anything, at least until they obtain their GCs.