Most large company hiring practices are not so much a selection of specific traits as they are a filter for ensuring a lack of negative traits. When you factor in the bias of narcissism in interviewers, you'll get competent people who are skillful at reflecting the interviewers' traits back at them (such as the author, who didn't demonstrate incompetency with his first answer, but aced the interview by reflecting the cleverness the interviewer must have self-identified with as "Google material".) After a certain point, four or seven or nine layers of interview will certainly guarantee the incompetent ones don't get through, but at the same time it will also select for the kind of highly adaptable social personality that is often found in political operators.
I saw something similar with a badly underqualified sys-admin who had been in marine recon before embarking on a technical career. He had zero issues finding a high paying job.
I read a book called "Money Ball" last year. One of the lessons I took away is that a successful baseball team can be created from undervalued stats (i.e. irrational beliefs in value cause inefficiencies). This trend you described forms teams of walkers xor home-runners, for example. I don't know why I believe this (I'm subject to my own criticism), but I strongly believe teams with multiple talents outperform teams with one talent (generalists vs niche).
Minutes? Well, yes.
In interviews, my tentative conclusion after two minutes is _usually_ the same as after 60 minutes. (I spend the following 58 minutes trying to disprove my hypothesis, of course.)