> Seems like the requirement of proving "there are or aren’t any residents or citizens that can fill the job" is going to be near impossible for the government to enforce
It's extremely easy to enforce with taxes that ensure the company is paying at least 1X0% of the highest market rate for the position. If they don't find an alternative to paying it is a necessary hire.
The requirement to pay market rate already exists and it's very easily gamed, eg. by under-leveling people or hiring them in under a related (but lower paid) role that doesn't reflect their actual responsibilities.
There's no premium financing proper adversarial regulatory agency there. If the IRS is not taking its special ~30% of 300+ workers salaries there's a best effort by a regulatory body that's viewed as a waste of tax payer money if it just checks a few technicalities.