They are issued two 6-month visas and four 1-year visas (not at the same time, but sequentially), where they must be employed at $100,000 or more and have no criminal convictions of any kind
If I were from another part of the world with the skills needed to earn over $100,000, then there's no way I'd accept this kind of deal. Trust me - the US is not the only good place to live that has good jobs. Other countries would give me better deals than 6-month/1-year visas.
I mean, really - you're saying make sure they live with those visas for 5 years and if they maintain all that, they get green cards. So highly qualified workers more or less must "suspend" their life for 5 years just for a green card? Because with one year visas, with the fear that it won't get renewed because someone decided the prevailing salary should be $98,000, no one is going to make any kind of long term investment. Have kids? Well, why should we move to the US and put them in a school where they may quickly get uprooted? Want to buy a house? Bad idea. I may get kicked out in 6 months.
but the real effect is that the $110,000 per year jobs would settle in around $100,000 per year, and immigrants looking to move to the US would aim for the $150,000+ jobs for the extra cushion.
That only emphasizes my point. I defy you to find someone who can thinks he/she can earn $150,000 and is willing to move to another country on a measly one year visa. Heck, if I'm worth that much to you, you better get me a green card in 1 year. Me? If I thought I could earn that much, I'd rather go to Australia, earn $120,000, and am almost guaranteed a permanent residency in 1.5 years than deal with snobby Americans and have the "privilege" of becoming a permanent resident. The Australians probably have better health care, too.
I just made up Australia. If not them, I don't doubt there would still be better options.