McKinsey is a management consulting company https://www.mckinsey.com/ which is famous (or infamous) for promoting highly 'streamlined' business practices. They're known for turning around failing businesses into profitable ones but also for the enron and 2008 scandals with the housing bubble. Though I'm not too familiar with exactly what 'McKinsey' would imply, it seems to just be a shorthand for whenever a business starts charging for something that was previously free. Aka luggage fees.

Possibly McKinsey & Company, the management consulting firm [0]. Read that article to see some companies its consultants ruined by recommending the wrong business strategy.

Also, from that link: McKinsey's alumni have been appointed as CEOs or high-level executives at Google, American Express, Facebook, Boeing, IBM, Westinghouse Electric, Sears, AT&T, PepsiCo, and Enron.

[0] https://en.wikipedia.org/wiki/McKinsey_%26_Company

McKinsey is a management consultancy that, among other things, often advocates costcutting through skimping on services, outsourcing abroad and currently, automating a number of auxiliary functions such as customer support and other cost centers.

Apart from what others said, Sundar Pichai was a management consultant at McKinsey before he joined Google.