"McKinsey receives about 100,000 per year."
Citation? That's highly dubious.
There are 111.5M adults in the US between age 22 and 55.
Of those, 64.9% are considered "participating" in the labor force. That brings us to 72.4M. Of those, 61% are considered "blue collar", i.e. manual labor. It's fairly safe to assume McKinsey isn't attracting that subset.
We're now down at 28M. Without further subdivision, I'm fairly comfortable in feeling skeptical that one in every 280 white collar workers in the US applies for a job with McKinsey every year.