What I find funny here (and on other tech sites) is that up until the moment you talk about H1B, everybody's all for opening up the borders and easing up on illegal immigration. It's all lovey-dovey "let's make them legal so they can pay their taxes" up until the point when they're actually legal and competing for the same jobs as the prevailent occupation as the community. But suddenly, as soon as the topic switches to H1B, it's a chorus of "don't let them in, they're stealing out jobs!"
From my experience with on- and off-shore consulting, the low-skilled jobs are the ones that typically get replaced. These are things from data entry to phone support. Companies that try to send away high skilled jobs tend to get burned by either the lack of talent, or the cost of the equivalent talent (cost accounting both for money and the necessary overall decrease in productivity). Which is to say, for a highly-skilled worker, whether somebody's on a visa or not, they're probably going to cost about the same.
Yes, some companies are switching fully to an on- and off-shore consulting work force. In the past, companies that have attempted this were ultimately forced to bring the majority of their skilled labor back because the talent simply isn't worth the additional hidden costs. Yes, there is talk (and fear, always a lot of fear) that companies will off-shore all of their tech workers. I think if anyone actually tries that, they won't be around for very long. And I'm not terribly sympathetic. There's no reason good people should hold up incompetent management, and the faster the free market gets rid of these companies, the faster more forward-looking businesses can assume their place.
There are, of course, two exceptions to this, that being the government and utilities. In this case, the Senators are investigating a utility. I expect both government and government-permitted monopolies (utilities) to be staffed by U.S. citizens. Even if they're contractors, which they usually are, I think that there is a national security matter at play, and that absolutely cannot be compromised by foreign, non-patrioted workers.
What I'm more concerned about is abuse of employees on a visa. Consulting companies tend to treat their visa-based workers well, but companies that sponsor tend to treat their workers like total shit. That's because companies that sponsor are able to hold that sponsorship over the heads of their sponsored employees. And people want to come here to work, and some of them are willing to do so for almost nothing. When applied in this way, work visas are nothing more than the modern form of indentured servitude. It's a human rights violation in our very own backyards, but because we're so concerned about job-stealing and keeping our jobs here, we can't even see it.
A brain drain from the rest of the world to the U.S. can only be a good thing. Sending menial jobs off shore is also a good thing. Letting tech-adverse companies die is or learn a harsh lesson is also a good thing. The only losers are the ones who can't keep up with the overall rising skill of the tech labor force. And quite frankly, there are plenty of on-premise jobs that simply cannot be outsourced for them too, though it may not necessarily be at the forefront of technology. The only bad thing is the use of having a work visa rather than citizenship to justify abuse. And that ties into a bigger issue of the Rights of non-citizens.
But I get it. People want their cake and to eat it too. Our in-house primary education system has churned out a generation of duds (now ever more than before, and it's only getting worse). We don't have in-house highly skilled workers anymore, just a lot of mediocrity burdened with significant higher-education-caused debt. To you, I apologize. The system deceived you. You shouldn't have gone to college, and never belonged there in the first place. You should have gone to trade school, or just gone straight out into the work force. If you want to take something up with the politicians, that's what you should make them address.