Seems like a solid change to me, without an obvious downside. (But I am not an expert and haven’t done any detailed analysis, so maybe this would have negative consequences I’m not anticipating.)
Another change that might be a big improvement, it seems to me, is to let H1-B visa holders more easily change jobs once they’re here, without so much risk or paperwork hoops to jump through. If it were easier for H1-B workers to switch jobs, then abusive employers would have less leverage to exploit them (forced overtime, below-market wages, etc.).
Machine shops fighting over top-1% welders with deep materials science knowledge should be no different to software shops fighting over top-1% developers with deep computer science knowledge.
I'd be much more willing to let people decide on their own:
Maybe figuring out a better alternative system would be a bit complicated, but it seems like it should be possible.
I certainly agree that the system could be rationalized, I've got a lot of my own ideas, but most reform in this area must pass through Congress. I've been paying attention to this issue for over a decade and half now, and one thing I've learned is that there isn't much enthusiasm on either side of the political aisle for major changes to the legal immigration system. Every once in a while a strong lobbying group will get a tweak or added numbers to a particular program, but the real political interest is the stock and flow of un- and semi- skilled workers from Mexico and Latin American.
I mean, if the Foo profession has huge salaries and crowds the Bar profession from getting any foreign workers... Did the nation really need to import those Bar workers that badly in the first place?
Carving out reservations for particular professions/industries is really just a big cake for lobbyists to fight over.
I think the far bigger issue isn't the professions, but the skewing effects of cost-of-living or non-salary compensation, or professions which our economy already doesn't value "appropriately" for some other reason.