I think we're making mutually reconcilable points here.
> Quality is distributed somewhat evenly.
Starting from that assumption (which I can agree with), here is a simplified (perhaps numerically inaccurate) argument. Assuming the top talent constitutes 1000 best researchers who have just graduated from their PhDs, and all relatively equally qualified, 500 US, 500 foreign.
There are 400 postdoc appointments. Currently if 200 postdocs are US and 200 postdocs are foreign and these H1B rules then inevitably disallow the next generation to have 200 foreign postdocs we still have 200 US postdoc candidates who are just as good and are still top talent.
You put in the assumption that they are all relatively equally qualified. I don't think the 1000 best researches are equally qualified. The x best are better than the 1000-x below them.
Additionally, if the exchange of postdocs is lower (many return to their country of origin), the research quality not only in the US, but world-wide will go down.
> Quality is distributed somewhat evenly.
Starting from that assumption (which I can agree with), here is a simplified (perhaps numerically inaccurate) argument. Assuming the top talent constitutes 1000 best researchers who have just graduated from their PhDs, and all relatively equally qualified, 500 US, 500 foreign.
There are 400 postdoc appointments. Currently if 200 postdocs are US and 200 postdocs are foreign and these H1B rules then inevitably disallow the next generation to have 200 foreign postdocs we still have 200 US postdoc candidates who are just as good and are still top talent.
Would this not still retain equal quality?