It’s amusing to see people try to give the Apple Watch and AirPods short shrift because they’re both extremely successful products that only look small next to the iPhone (and ignores Cook’s role in that as well). The Apple Watch is bigger than the iPod at its peak and is something that actually makes a dent in the universe at a level other Apple products don’t. There have been dozens of stories about customers and their Apple Watch saving their lives or alerting them to a latent medical condition [1].
To understand Tim Cook’s importance to Apple you have to understand that Jony Ive was already at Apple for several years before Jobs returned and Apple was headed to bankruptcy. Cook is who actually built Apple into the machine that could execute, and it’s why he was officially named CEO in 2011. He was the unofficial CEO for years before that.
Actually it’d be more accurate to say he’s a founder of Apple 2.0
[1] https://9to5mac.com/2019/07/19/apple-watch-prompts-heart-sur...
Jedberg's point is that strong operational CEOs are great at getting more users for existing products. Visionary CEOs are great at inventing new products that can capture new markets the company hasn't previously been in before. The only major new product Apple's introduced under Tim Cook's tenure has been the Apple Watch, which in actual usage is more like an accessory to the iPhone than a new product category. He did a great job growing Apple's existing iPhone, iPad, and Macbook businesses, but a less great job introducing new ones.
See also the a16z essay "Ones and Twos":
https://a16z.com/2010/12/16/ones-and-twos/
Cook is a Two, as are Eric Schmidt, Sundar Pichai, Steve Ballmer, Sheryl Sandberg, and Dara Khosrowshahi. Ones include Steve Jobs, Larry Page, Sergey Brin, Andy Rubin, Travis Kalanick, Bill Gates, and Mark Zuckerburg. Nadella is shaping up to be a One, though I'm not entirely sure on this (I haven't been following Microsoft closely).