I feel like a big concern could be resolved by creating a new type of visa for students who studied in the US and now want to work there, rather than a general foreign professional visa.
All of this should to a little extent alleviate some of the concerns.
The weighted system should still work since the candidate pool (from within the US) is likely mostly students on OPT. They should have comparable salaries, unless they are hired by rotten companies.
Students have the fewest skills, if we are to have a work visa program it should be targeted at high skilled laborers, who have worked in industry for enough time to pick up desirable skills
studying here is no guarantee you'll get to stay, even if you did a phd.
That’s not to say that all US schools are good or equal, just that the credential is easier to validate.