I think it's interesting that the author writes extensively here about the relationship between hierarchical rank and income without mentioning the actual trait that most reliably predicts the ascension of hierarchies: ambition.
I've written about this trait before (1) and was expecting it to be explored with the mention of "trait" in the title (which typically refers to temperament or personality). More ambitious people consistently pursue roles that beget status, authority, and income opportunity. Ambition, which is a combination of traits in itself, reliably predicts actual outcomes like educational achievement, the pursuit of more prestigious occupations, career advancement, work output (per the author's mention of working full time vs part time), etc. While the research on ambition is admittedly fragmentary, it's safe to say there is more than purely an economic angle to this conversation.
I've seen ambitious people that are also competent, and I have seen ambitious people that are are not very competent. It is hard to work with the latter kind. It's usually a lot easier to work with grumpy but competent people who actually have some realism. If they say something, it's worth listening.
In a working meritocratic organization, competence is recognized and rewarded. Competent people have a lot of projects that they can choose from. Competent people want to work in meritocratic organizations. They can switch jobs until they find one. Organizations with a lot of competence tend to do well. Owning stock for example then becomes quite profitable.
So maybe it's not all about ambition or climbing the ladder...
I am painfully technical and throughout in what I do and this has me pushed up the ladder usually against my will. My company wild prime me without telling :)
I hate management (and am bomber about that) so I always had a tiny tell and was happy to oblige of someone in said y'all wanted to make and go that path (two successfully did)
I am now an SVP in a very large European company and remind everyone that there is supposed to be a "technical ladder" for people that "lack ambition in management" (said my teenage son about me, he just does not understand how I can mis such opportunities).
Ambition for me is to coach people and always understand what they are saying. Or help to promote the good ones, or help some to realize that management is a pain in the ass when I realize that they are like me (just 30 years younger).
Ambition is not always to get a better sounding title or be closer to the CEO.
Do you have any non-anecdotal information to support this theory?
It's definitely within reason to reframe ambition as "willingness to take risks to advance oneself." In which case your theory might be suffering from survivors bias. Given a number of people pursuing ambitious agendas the average and median results could be anywhere on the map but you would still have an outsized representation within "people who ascended hierarchies".
There is also a good amount of literature around "achievement motivation," which in many cases is a surrogate term for ambition in the research context although the argument can be made that they are not completely synonymous. However they generally reach the same conclusions. Also the underlying causal factors related to ambition - high conscientiousness and extraversion, low neuroticism, higher general mental ability, etc. - predict higher achievement outcomes in research as well.
I've written about this trait before (1) and was expecting it to be explored with the mention of "trait" in the title (which typically refers to temperament or personality). More ambitious people consistently pursue roles that beget status, authority, and income opportunity. Ambition, which is a combination of traits in itself, reliably predicts actual outcomes like educational achievement, the pursuit of more prestigious occupations, career advancement, work output (per the author's mention of working full time vs part time), etc. While the research on ambition is admittedly fragmentary, it's safe to say there is more than purely an economic angle to this conversation.
(1) https://www.bringambition.com/post/what-is-ambition ; https://www.bringambition.com/post/history-of-ambition