There is no shortage of skilled tech workers. There is a shortage of skilled tech workers willing to work for minimum wage.
My brother-in-law's daughter is graduating with a basic 4-year degree in June and ALREADY has a 6-figure job lined up with Cisco. Her brother graduated 2 years ago and snapped up a 6-figure job with Google immediately.
It doesn't sound to me like they're passing over Americans to get foreign minimum wage workers.