People who can actually penetrate stuff "by hand" do exist, and I'm one of them, but how many of us work for pentesting companies? I don't think the money is there, mostly, because clients are wary of buying snake oil and because clients don't actually need real live vulnerability exploits. The pentesting clients just need to close holes, or at least satisfy an insurance company that they did so. Pentesting clients want to certify compliance.

I put a "by hand" job posting in the "Who Is Hiring?" thread. Here: https://news.ycombinator.com/item?id=19543995 It isn't anything I'd call pentesting. We study software, not specific installations of software.