That's the canonical example, but it's not about age in and of itself, but the gap between the CEO that turns them from a person into an idol. It's often an age gap (especially in the past) due to the culturally-entrenched ideal of automatic respect and deference to one's elders, but it can be any gap that makes the direct reports feel like they are somehow inherently beneath the CEO in ways other than corporate rank.
The point of that sign is that the CEO's direct underlings can't even question the CEO's choices.
It's not just their direct reports or even their employees. HN, Twitter, and Reddit are full of commenters simping and white-knighting for CEOs they have no relation to, whenever someone questions them. Corporate leaders have become this weird "priesthood" complete with followers and apostles praising them online.
I think ' a generation older' is really just a proxy to explain the social dynamic of "subordinates are unwilling to question the authority of the CEO"
Seniority can be only a part of it. A CEO who is extremely wealthy and who is an actual celebrity does not like being told "no" to. It only gets worse with time - as they begin to think they are uniquely brilliant (and funny).
