"I'm not smart enough" is not always a cop-out, or "a (lame) excuse". It can be a sign of maturity, and a cause of significant respite. Knowing your limits allows those who are intellectually limited to pursue tasks suitable to them, and still be satisfied with life (even though they haven't created Facebook or Pinterest).
Even for the more gifted of us, knowing your limits might lead to a happier life..
This whole mentality that everybody are born equal in mental capacity is a likely cause of stress and depression among many people today.
People are born tall, small, fat, skinny, smart, supid. Just find your level and optimize your own happiness.
Fast forward. Now my wife is in school and she studies like crazy hours every day and still doesn't absorb the material well. It takes her tremendous persistence and she is frustrated by people in her class who, like me, could just roll in having glanced over the material and do well.
That said, I agree with the meat of the article. I used to say "I'm not smart enough" to do things like work at "Big Software Corp" or invent novel algorithms, etc. Now I'm more honest and I'll admit "I'm too lazy" to do those things.
I used to think that too. "I'm just too lazy". But in comparison to what? The protestant work ethic? Are you really "too lazy" or is it just that you're happy with who you are but like everyone else are still bullied by societal pressure into feeling guilty for not wanting "more" or having more ambitions?
But to your point, engineering is just persistent and consistent effort. Most people don't want to put the time and effort to really learn the science.
Also keep in mind that the person saying it may mean it more as flattery - i.e., it may be a polite lie and they don't really think that. And of course, "I'm not smart enough to do that" is more polite to say than "that sounds boring and I'm super not interested".
For example, I wouldn't know how to do face recognition quickly. But thanks to OpenCV and QT, I was able to make https://github.com/jwcrawley/uWho
I leveraged the code that was written to allow me to go a tiny bit further.
Or are we so politically correct now we can't acknowledge variation in mental capacity - particularly working with numbers and logic.
I think it's maybe 10% intimidated, 10% lack of motivation, 80% not smart enough.
Also, anybody thinks that being smart is mostly the result of removing complexity from your brain ? There's nothing 'more' for you to do or have, but to let the idea sink and reorganize your mind with a simpler thus larger concept.
All people hear is the Computer Science part and every conversation people say, "Oh you must be smart," or "I could never do that."
My response is always, "Nope I am not crazy smart. I just really love computers and I keep at it." People always associate CS with being a genius, I am no genius. I am just a hard headed guy who loves computers, and will always keep trying to get better at whatever I am doing no matter how many times I fail.
I'm a backend/appsec guy. No way in hell would I do that. It would be arrogant and end in disaster.
That's what teams are for.
It wouldn't surprise me if that was the case for at least some of the people described by the author.
If they don't feel smart enough, maybe what they mean is that they expect to end up on the bottom of the status hierarchy. And that might be a bit too rough to want to go through with. Especially if you have other interests, aptitude or talents.
[1] Yeah, umlaut-fail.