So replace hiring managers with competent staff who aren't feeding resumes through a filter.

The problem is that "competent staff" are still under conditions of low information, deluged with resumes from unsuitable candidates, and lacking suitable discriminating power between the resumes they do see. I'd encourage you to look through 100 random resumes online and try to decide who you'd hire; most likely, you will pick someone like yourself, not someone who's best for the job. In other words, don't hate the player, hate the game, because otherwise you will end up hating yourself.

I think what's ultimately needed is a way to reveal more information about a candidates' abilities in a very short amount of time. Contract-to-hire works for this, but has the problem that many candidates (and in particular, good candidates) don't have time to devote to a project that may lead to a job. So does tokenadult's persistent suggestion of a work-sample test (and HireArt's implementation), but these both have the problem of being able to cut down an employee's daily duties into a small problem that can be given as a short task. Many of the skills that a really experienced employee brings to the table are only evident on long, hard, extremely challenging problems.

What is ultimately needed is a renewed understanding that personal contacts are what are important and for both hiring managers and potential employees to seek out these kinds of connections.

That's precisely what LinkedIn is for.