Part of the problem is that a CEO plays a very different role in a three person company, a 300 person company, a 3000 person company, and a 30k person company. I have a very difficult time imagining swapping out the CEO of an early round startup without having a major existential crisis.
To that I agree. I wasn't talking so much about startups.
Admittedly a CEO(quite often a founder) there plays a much more instrumental role.