I don't work in programming, but "you can do hard things" applies to my work as well. It drives me nuts when coworkers refer to me as really smart when in fact I'm merely curious. "I have no idea how you did that!" You should ask. That's how I learned it.
In my experience, curiosity and intelligence are very strongly correlated. There is a real gap between people with the curiosity and ability to explore and learn, and people without. This is often handwaved as "motivation" but it's more than just that.
In fact, the gap is so large that it can be really hard for a person on one side of it to understand how people on the other side think.
I think part of it is that geniuses gets (or at least feels) rewarded whenever they try learning, while other people might not. For the same amount of effort, the amount of new knowledge gained by other people is fewer than what geniuses can get. Overtime, leaning no longer feels worth it. Thus normal people no longer feels curious while geniuses still do.
I thought of it from the other end. Curious folks end up engaging in cycles of formative learning that the less curious do not. The perceived intelligence follows. Its the process that makes the difference.
People who cannot learn hard things don't have time, or they think they don't have time. Actually they try to fake their way through because they believe it is impossible or at least too late to sort things out properly.
The so called geniuses seem to have rather lax lifestyle, like free evenings to really make their homework. When you constantly think you're in hurry you've pretty much lost the game. You're just trying to get by and learn very little.
This is true, you only grow when you have nothing to do. At least, nothing that other people are telling you to do. If there's something you want to learn really bad I highly recommend taking a sabbatical and just spending the whole year learning that topic deeply. You can get to the bleeding edge of most topics in one year of study, especially ones adjacent to what you already know. I did this in my 20s and can't wait for the stars to align to be able to do this again.
My experience: I often thought that I didn't have the time to learn (hard) things, only to find out sooner or later that I actually did, and still do.
At work, this usually meant that I was giving myself tighter deadlines than they needed to be, or that I was putting too much effort into tasks nobody cared that much about. Over time, I learned that it's OK not to put 100% of energy into the assigned task. Sometimes, it's even encouraged to use that extra energy to learn.
Arguably, I did have the privilege of starting out in salaried European office jobs, where there are more robust boundaries and opportunities. It's obvious how precarious physical work discourages this kind of learning. And reading comments like yours, it's clear how lucky I was to have managers and environments that didn't exploit my eagerness to put pressure on myself.
But if you do have an opportunity to make adjustments, I'd suggest putting less pressure on performing like an athlete, and channeling that energy into learning opportunities instead. Rarely will anyone carve out time for your learning, but they may be responsive to your request or boundaries.
