H1-B, as championed by Microsoft and embraced by many large companies, was clearly used as a tool to replace market wage tech employees with low wage immigrants. Microsoft's arguments before Congress were fully debunked, and many of us who have worked for two decades in US IT have seen the reality.

Plus, over the last 15 years as what we do with and demand from computing technology has expanded exponentially, the knowledge gap between management/hiring managers and IT workers has grown to the point where management often has no clue at all about how to spec a job or how to filter/evaluate a candidate. This has led us to the alphabet soup that is job specs - the "what did our last guy do before he quit? yeah put all that on the list of requirements" problem.

So it's not just an H1-B problem; it's much bigger. But it probably results in a feeling of futility on the part of hiring managers, leading them to think, "well since we're basically guessing at this hiring thing, we might as well hire the cheapest we can get."