I have never heard anyone claim that McKinsey is a purveyor of quality shovels. My impression is that they're corporate parasites who contribute little of value.
McKinsey and the others are good at selling solutions to a C-Suite that keep those jobs, because they're seen as the client, whole stripping out the workers who actually add value. The consulting does it's job, secures the decisions that protect the bosses, and in doing so often ruin the companies they're there to "help".
