If employers can't pay the market wage, they can't afford a worker. This is what drives productivity gains for the economy. Inefficient business models die off and are replaced by businesses that can use labor more effectively.
Note that there are also plenty of other factors besides wage, eg. 24/7 on-call, working in a remote location, mandatory overtime, etc. Even if an employer actually is paying the market wage for the general job category, there is likely a reason why American candidates are not interested.
No, there's no contradiction. Again, you and others seem to be assuming--without evidence--that for any given job opening, there is an additional qualified local resource available in the prevailing wage band. But that's not necessarily the case. You don't have to take large tech companies' word for it; just ask small business owners around you.
I have a degree in Economics. This is a theory, and theories don’t always 100% match reality at the microscopic level.
> for 99.9% of jobs there are plenty of qualified American candidates who can be hired for the right price.
You keep making the mistake of positing facts that are not established. We’re done.
In this entire comment thread, you have not managed to name a single example of one of these mythical impossible-to-fill jobs.