What about non-tech workers that come to the US through an H1-B? Scientists come to mind. If you don't have a PhD, your starting salary isn't going to exceed $100K. Are they just out of luck?
There's already a good number of US-citizen PhDs in non-CS/"tech" fields who are being underutilized. Perhaps such moves will help prioritize them and adjust some of the supply/demand issues.
Not all PhDs are equal. You're not hiring them to flip burgers at McDonald's
That's a gross generalization. Plenty of unique overseas talent could not be utilized at $100k minimum. Translators, for example.
Outside of very high cost of living cities, probably yes