I mean no need to spread misinformation. This information in easily verifiable.
Sundar Pichai, Google's CEO, worked at McKinsey for ~2 years and then joined Google in 2004, eventually working his way into the position of CEO.
Pichai's fuck ups are unlikely a result of McKinsey, at least not directly. That isn't to say that McKinsey is completely off the hook. They work with plenty of "top" companies and I'm certain Google is one of them.
McKinsey likes to hire recent graduates who they suspect will wind up in high places. It builds them strong connections and lets them brag to potential customers as well as customers' stakeholders that they have cutting edge talent and that they hire the best and to tell potential employees that a few years with them is part of how you move from an elite educational institution into high levels of business or politics.
The worst thing this says about Pichai is that he was the sort of person who seeks to be on the ladder to elite careers.