In my experience, this "avoiding the Peter Principle" is rare for people who are founders/friends-of-founders.
I think that's where the complaint comes from. It's mainly that a lot of competent people get skipped because founders and friends of the founders keep just hiring their external favorites rather than promoting and rewarding people who are getting the company to where it is.
What's your sample size? I mean sure, nepotism happens, this isn't a surprise. But for competent founders, the ability to successfully execute the role at hand is the primary consideration. To be coldly rational about it: whether someone was a high performer at the previous stage or if they were a close personal friend are both irrelevant data points. The only thing that matters is can they be effective in the next stage. Obviously this is a judgement call, and founders can get it wrong (they're only human after all), but the Peter Principle is a real thing and it can be deadly when someone is promoted beyond their capabilities during hypergrowth. This can be a very tough pill to swallow for someone who got the company where it is, but it doesn't make it less true.
I think that's where the complaint comes from. It's mainly that a lot of competent people get skipped because founders and friends of the founders keep just hiring their external favorites rather than promoting and rewarding people who are getting the company to where it is.