I look at it from a perspective of interchangeability - if you swapped Steve Ballmer in for Cook, nothing much would have changed. Same if you swapped Nadella in for Pichai, or Pichai for Cook. Very few of these men are exceptional; they are ordinary men with exceptional resources at hand. What they can do, what they should do, and what they can get away with, unseen, govern their impact. Leaders that actually impact their institutions are incredibly rare. Our current crop of ship steadying industry captains, with few exceptions, are not towering figures of incredible prowess and paragons of leadership. They're regular guys in extraordinary circumstances. Joe Schmo with an MBA, 120 IQ, and the same level of institutional knowledge and 2 decades of experience at Apple could have done the same as Cook; Apple wouldn't have looked much different than it does now.
There's a tendency to exaggerate the qualities of men in positions like this. There's nothing inherent to their positions requiring greatness or incredible merit. The extraordinary events already happened; their job is to simply not screw it up, and our system is such that you'd have to try really, really hard to have any noticeable impact, let alone actually hurt a company before the institution itself cuts you out. Those lawyers are a significant part of the organism of a modern mega corporation; they're the substrate upon which the algorithm that is a corporation is running. One of the defenses modern corporations employ is to limit the impact any individual in the organization can have, positive or otherwise, and to employ intense scrutiny and certainty of action commensurate with the power of a position.
Throw Cook into an start-up arena against Musk, Gates, Altman, Jobs, Buffet, etc, and he'd get eaten alive. Cook isn't the scrappy, agile, innovative, ruthless start-up CEO. He's the complacent, steady, predictable institutional CEO coasting on the laurels of his betters, shielded from the trials they faced through the sheer inertia of the organization he currently helms.
They're different types of leaders for different phases of the megacorp organism, and it's OK that Cook isn't Jobs 2.0 - that level of wildness and unpredictability that makes those types of leaders their fortunes can also result in the downfall of their companies. Musk acts with more freedom; the variance in behavior results in a variance of fortunes. Apple is more stable because of Cook, but it's not because he's particularly special. Simply steady and sane.