If a 5K of 12:57 was really "10X", an average runner would take just over two hours. That performance is nothing like 10X.
How much faster would John Carmack produce a new graphics engine than a recent bootcamp grad? How much better would Carmack's be?
I know I've gone to unfair extremes with the question, but it still illustrates the point. Really excellent developers are waaay more productive. The upside is huge. All the time saved avoiding blind alleys based on experience, all the cases where experienced intuition identifies the cause of a bug that would have taken much longer, etc.
To carry the analogy forward, a 10x runner might take a shortcut, use a better implement to complete the course, etc.
Physical capabilities of organisms (e.g., strength, speed, jumping height, etc.) tend to fall into normal distributions.
Knowledge work where you can take advantage of powerful (mental | software) abstractions don't tend to fall into normal distributions, as previous work can make a bottleneck disappear, leaving you with more mental bandwidth for other concerns, which quickly expands your capabilities.
I'm talking about productivity in knowledge work which is different.
Now in chess, as in programming, there are clearly some individuals who excel by orders of magnitude over beginners and even average competent players. But because of the vast scope of possibility, programming "grandmasters" will do things that no one else could have even thought of in one domain, while in unfamiliar domains they might require a good deal of study before they surpass the average journeyman practitioner.
Meh, analogies suck.
Perhaps this is a true statement; however, I have no doubt that 10x programmers do exist who do not build technical debt into the application. Some people really are that good. I don't think the average person realizes exactly how good the best in the world are at what they do. For instance, I ran track for 8 years and competed in college. You don't realize exactly how insane a 12:37 5K is until you've trained as hard as you can for years and you're not even close to that time. Nor do you realize how difficult a perfect rendition of Liszt's transcendental etudes are until you've spent years trying to learn them on your own. I imagine the best programmers in the world are similar, but it would take the average programmer decades of programming before the magnitude of the skill gap becomes evident.