Knowledge work is typically creative, the right model is an art studio, a
    movie set, or a band.

    Knowledge workers aren't cogs, they're part of a team.

And if you look at how bands, movie studios, art studios or professional teams hire, it bears little to no resemblance to the hiring process described in the OP's article. All of the professions you describe hire through some kind of auditioning process. No sports manager would hire a star player on the basis of, "Do I think this person is a cool person?" No movie director would hire an actor on that basis. No art studio would hire a painter based upon a description of their personality. All of those places would judge a person on their portfolio, or an audition.

And that's exactly what those "silly" whiteboard puzzle problems are. They're an audition. Just like actors who have to say silly phrases with emotional inflection, just like bands that require new members to play some random short pieces, and just like football players who have to post their times on 40-yard sprints. Now you can argue that the auditioning process should be improved; that right now the skills exercised with the audition aren't the same ones used by a working programmer and I'd agree with you. I do feel like the process of auditioning for a software development role can be improved. But the way to do that is not to abandon the process entirely and just go with some kind of ill-considered gut feeling about "how much do I like this person?" The way to do it is to make it such that the interview more closely resembles the job the person will be asked to perform.