I'll be honest that I read a different article on the same topic and did not know about the salary floor. So I wasn't thinking about that. I'm... mixed on that, but it does add a wrinkle to the equation.

I prefer a purely compensation relative approach because it let's the market decide what the actual salary for a software engineer is (with a percent of compensation premium for a foreigner and a 0 extra cost for a native). The market can dynamically adjust what a software engineer makes (not fixed price control) but it just cost more to hire foreign people.

In direct response to your first sentence, I think even foreign workers (who largely work harder and have more on the line than domestic workers) would question the wisdom of working for 50k a year as a software engineer in the US. They are actors in this system as well, and you can't just assume that you could offer 50k and get them to accept.