Earlier quoted context omitted.
Here's the problem from the company's perspective: You get thousands of resumes, and you can't possibly call every one of them. So you try to find ways to build a funnel, hoping that your heuristics are weeding out the majority of those who are unsuitable for the position and keeping the majority of those who are suitable. It's not that the company is being a dick, or that they don't value the candidate's time; it's…
If there is such a scarcity of software engineers as companies claim, then what haystack?
It's hard to grok how difficult and complex hiring good people is until you find yourself on the hiring side of the equation. The leaked Valve manual does offer some insight, but even that's barely scratching the surface.