Please recall the entire context:
Thiel stated early and often (as Facebook's earliest investor) that he would stand behind Zuck retaining majority control. Based on this support there was no other option than to provide Zuck with all the support, mentorship and education he would need to scale along with FB.
Zuck had unflinching VC support :)
I'm not convinced. If you look at the big ones like Amazon, Facebook, Apple and Microsoft, they kept their founder until big except Apple where they kicked him out, went pretty much broke and then got him back and then recovered.
There are also many examples where the founder was kicked out and the company tanked but it would be hard to distinguish cause and effect there - maybe they were fired because the company was doomed. I find it hard to think of any where they achieved great success by firing the founder(s).
Managing a large company is a skillset but you can hire for or learn that.
Having the vision and drive to start and build a company is also a skillset, and one that's much harder to hire a replacement for.
By the way The Hard Thing suggests hiring experienced people to help the CEO, not replace them.
Your statement contradicts itself. He was not about to be fired, his legal standing guaranteed that could not occur. The investors and board fully understood the context the entire time, they invested knowing that it was Zuckerberg's kingdom. Besides, he was the board legally.
And honestly, they should. Managing a company through 50, 100, 150, 500 and 1,000+ employee milestones requires very different leadership skillsets. There are very few founders who (1) understand this (2) are willing to party ways with their company (3) can navigate through each stage without help and (4) would pull a Zuck and surround themselves with more established/senior people (e.g. Sandberg) as they hit those milestones.
I'm all for young entrepreneurs challenging the status quo by thwarting an old guard of seemingly "old people" (a la Jack Barker), but this is one area that traditionally has a lot of "old people" simply because experience is incredible valuable to scaling companies.
I haven't read "The Hard Thing About Hard Things", but my understanding is that it basically touches upon all of the intricacies of how to navigate business challenges that typically more experienced senior individuals possess.