To an extent, it really isn't hard to be a 10x programmer.
Take, for example, the median level 1x programmer. Perhaps a Java programmer working at a large tech corporation on a team of 1000+ in Indonesia or Brazil.
That guy isn't visiting HN. That guy doesn't read tech articles at home. He may join a few programmer groups on Reddit or Facebook. But his main concern is that he gets paid and feeds his family. He doesn't care so much about doing his work well, but he cares that he does it well enough to make a 10% salary raise each year.
He can probably reverse a linked list. But his searches are all O(n^2), and he can't do any less. The company that hires him doesn't really care - they're unfamiliar that things can be better, and as far as they know, they'd rather get hire ten $15k guys than a single $150k star programmer.
Is it possible to code 3x faster than that guy? Certainly. Especially when it comes to harder parts of the work.
Is it possible to code 3x better? As in code that's more efficient and doesn't crash as much? Also very likely.
And someone who codes 3x faster also reduces the cost of the project drastically - you can pay a team one month wages instead of three.
Now you put these multipliers together, you get easily more than 10x, quantifiably.
Sports players may try to run 100m a second faster, but star programmers can easily build a project faster and cheaper.