Google's recruiting system isn't "failing" unless they're hiring unqualified devs. Google gets tons of applicants. The point isn't to prevent qualified applicants from being rejected, it's to prevent unqualified applicants from being hired. They can do whatever arbitrary, unfair filters they want as long as they still have at least some applicants left, and as long as those people are adequate.
Every time there is a thread on HN where people are debating the right way to filter applicants, the premise that goes unexamined is that there is one optimum, whether it's Google's procedures or something else.
But it's not just Google that can't hire everyone qualified. It's every employer.
Say, for simplicity, that any employer is only able to hire 1% of their applicants.
If they all used some optimal procedure, then they will all be fighting over the same 1% and the other 99% will be unhireable and start a revolution or something.
This is inescapable, I think, no matter what the so-called optimum is. It's like...a Doomsday Schelling Point.
Each company can disregard the fate of those filtered out, but only if their methods are sufficiently diverse.