There's a side-effect, however, that's being ignored.

If US companies don't like/trust the talent coming out of US colleges, they should have a stake in improving those programs. But if their solution is just to hire immigrants, it cheats colleges out of feedback from industry.

Colleges really need more practical courses, at least starting in upper years, that set developers up for success in the workforce. How many devs today come out of college needing 3-6 months of learning just the basics? That shouldn't be happening.

That's true of pretty much every engineering discipline. You may disagree but university engineering programs, especially at the better schools are not designed as job training programs. Personally, I don't think they should be. The hot technologies today will be last year's news soon enough. For companies that really do want to hire people whose training is focused on the practical, there are always code camps and other professional programs.

University isn’t a job training programme or a trade school.

The best engineers I have ever worked with have been American.

They are probably not representative of the average.