Some of us don't choose our beliefs based on what is most convenient or most beneficial to us. Instead, we try to see the world for what it is, truthfully (or as close to a true representation of the world as it's possible to get, anyway). If having a realistic worldview hinders my ability to learn, then so be it. Not everything is about maximizing productivity.
I think the point is that the worldview you described is not realistic.
Many people are successful because of hard work and dedication. Sometimes having talent in a tangential field (design, reading, being a good listener) is enough to make you an excellent engineer or team member. Success is complicated and often depends more on the world than on your particular attributes. Example: Maxwell was a true genius, but he had Faraday's life's work to read through. Faraday was a hard worker and a meticulous note taker who didn't really know math, but without his work Maxwell would not have been able to write his equations. Can you imagine if Faraday gave up science because he wasn't good at math?
Furthermore, the poster has very clearly expressed in subsequent posts that they don't believe talent ("innate ability") exists. I strongly disagree with this idea as well, and there is a mountain of evidence to support my position.
Nope. Just because it says so in a book doesn't make it true. When you make a statement of the form "X does not exist", a single counter-example is sufficient to prove you wrong. Lucky for me, many such counter-examples exist, and many have even been discussed in this thread. I'll add one to the list: tourist (Gennady Korotkevich). He's a competitive coder that's several orders of magnitude (e.g. 1000x) better at coding competitions than the average competitor. And the average competitor is a few orders of magnitude better than the average professional programmer who doesn't have algorithm experience. All of this is measurable (at most we can quibble about whether the skill differences are 100x or 10000x or infinite). If you don't believe me, please go and take a simulated Codeforces competition right now and see how long it will take you to solve some set of problems that tourist solved in under 2 hours (or if you will be able to solve them at all - I certainly won't be able to solve the hardest Codeforces div1 problems no matter how much time I put in).
I have a feeling this mountain of empirical evidence was insufficient to change your mind about this. I would appreciate if you could take the time to explain why? Why is this evidence not enough?
For example, here's my Codeforces profile: https://codeforces.com/profile/baobab
Started in 2015, plateau'd in 2016 and no measurable improvement from subsequent 3 years of practice and study.