The scope of my argument is narrower than you're making it out to be. Letting in immigrants with tech skills would definitely hurt engineering salaries. Would it help the average person who doesn't have a VC fund? Possibly, but deciding that point involves a lot more assumptions about the nature of things.
If all occupations cooperate and allow greater competition in their respective fields, then the net wealth effects on the economy are positive. If one occupation blocks competition, its members may benefit relative to other occupations, but there is no reason to assume that only one occupation will be able to defect, and encourage a policy decision that benefits its members.
One of the ways to counter the inevitability of actors making rational decisions that end up making everyone worse off is through the setting of effective public policy with an eye to aggregate benefits.
I think it is very safe to assume that the point of funding engineering education was that engineers' work is valuable to society, not that people who can make it through intrinsically merit certain salaries. If acquisition of talent through immigration is another channel, so be it.
The idea of education subsidies is also interesting to consider. On one hand more people are able to choose the career, so the skills are less scarce, and salaries are lower. On the other hand the increase growth in the community of trained people allows for greater sophistication, cooperation and specialization, which leads to more valuable output, and higher salaries.
Letting in immigrants with tech skills would definitely hurt engineering salaries.
Not necessarily. Letting in immigrants with tech skills to compete with software developers should reduce salaries. But letting in immigrants with tech skills to found companies should drive up demand for software developers.
Letting in immigrants with tech skills would definitely hurt engineering salaries. Would it help the average person who doesn't have a VC fund? Possibly, but deciding that point involves a lot more assumptions about the nature of things.
What assumptions? Do people who are neither software engineers nor VC fund owners not own cell phones? Do they not use Google and Facebook? Etc. etc.
