You have brought up something that most Americans don't want to hear i.e. "The Truth"! I have worked for well over a decade in the US (but i did not study there) and had always wondered about the dearth of "Americans" in the Tech. Industry. Here is my blunt assessment;

1) Your entire culture/society has turned away from STEM fields. Everybody is only interested in making money via Media/Management/Finance and any other way to "get rich quick". The pursuit of knowledge is gone. This is quite sad given that your previous generations did much to develop and spread scientific temper throughout the world.

2) Americans also suffer from major self-entitlement. In a global world, the fact that your previous generations were scientific top-dogs does not guarantee you the same status without working for it. You have to compete and prove yourselves worthy. So when the industry brings them face-to-face with reality they lose heart and start blaming everybody else for their predicament.

3) Americans are averse to hard-work. Here the Chinese/Indians wipe the floor with them. It is a standard joke in the Tech. Industry that while the Chinese/Indians do the actual work, the Americans are only good for bullshitting in Management/Marketing/Sales roles. Whatever happened to the "American Work Ethic"?

4) It is now a truism that much of the Tech Industry work has been "commoditized" and the barrier to entry has gotten lower. Most workers are mere "Craftsmen" rather than "Engineers/Scientists". For example, i have worked alongside PhDs in Physics/Mathematics/Biology etc. and their output was comparable to mine (no PhD) simply because the domain did not need their specialization. Most of the Software Industry is like this.

I just wish that the current/future generation of Americans would take a good hard look at themselves and make the necessary changes to their society to build themselves up again instead of blaming "immigrants" and everybody else.