I think the difference between 1x developers and 10x developers is that 10x developers either have an in-built aesthetic of good code which drives them to have the other characteristics you list or they happened to be employed in a codebase that was well-structured early in their career. I think the problem in the industry is that most codebases are cesspools, and someone who has only lived in a cesspool won't know there's anywhere to escape to (so they won't exert a lot of effort trying). Someone who can see an escape, even if it's only in their imagination, will work very hard to get there. Another place people fall back into 1x is when they try and fail to escape and get slapped down for the attempt.