Who defines “profession” though? Is “farmer” all encompassing, or is “chicken farmer” different from “cattle farmer”? Is “battery chicken farmer” different to “free range chicken farmer”? Do I need to be top 5% US-wide or just the city/state I would be hired in?
I don't disagree there's a lot of complications in the actual implementation, but this approach is a better-than-status-quo way to achieve some fairness IMO. Currently the US Dept of Labor has a system of determining the fair wage that should be paid to a certain job description at a certain geographic location. In the green card process this is called "prevailing wage determination". Why not use it for H1b too?