Then, this comment that I'm currently replying to, pins most of the responsibility on not "having the genes for it."
Your HN username also leads me to think you have a "fixed mindset" around your capabilities.
Regardless of to what extent (1) and (2) impact general career success, I suspect your mindset is a self-limiting one. For example, even if 80% of a person's success was determined by their genes and pedigree, and only 20% by their personal effort or resourcefulness, I suspect the mindset you have is to focus on lamenting the fact that you don't have the 80% and neglect the 20% you do have control over, leaving it on the ground and thereby reducing your own chances of success. It'd be a little bit like someone who wasn't born particularly tall, saying "Well, what's the point of drilling dribbling, passing, defending or shooting? There's no way I'll ever be the world's best player with genes like mine?" resulting in a self-defeating and self-fulfilling prophecy of failure.[1]
I don't want to come off as a preachy person on the internet to someone who I don't know, but if I could make a suggestion I would be curious for you to introspect as to why you may have this worldview. Folks I know in real life who have a mindset similar to those expressed in your comments often seem to feel insecure, unconfident or otherwise engage in self-shaming and constant comparisons with others.
[Edit] In the spirit of sharing, I will confess that that your mindset also reminded me of mine when I was in college. I had gotten rejected from a large number of universities I wanted to attend, and had only gotten into my state university. My peers and friends from high school largely went to prestigious brand-names.
The insecurity gnawed at me and made me engage in many foolish behaviors during college, and also caused me to constantly compare myself with others. I was ultimately very unhappy.
Through a series of experiences (i.e. therapy, honest introspection and self-reflection, conversations with trusted friends, being challenged on my mindset by others), I slowly came to understand how my mindset contributed to the same failures I was complaining about.
It's been over a decade since then and I have long since shed the mindset that held me back then, and am much happier for it.
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[1] Even this example is probably inaccurate because it draws from a domain where genetics play a larger role than I think they do in professional success. I suspect many attributes of a successful professional come from behaviors and tactics that are learned through social mimicry and learning from others rather than some genetic predisposition towards e.g., being thoughtful, being articulate and concise, running effective meetings etc.