Please learn to write

There is very little automation required in writing, though.

Writing is for people, not compilers, and people don't like reading the same thing over and over yourself. Good writers don't repeat themselves simply because it's boring (except, of course, in situations where it makes sense to repeat yourself for some specific purpose, but I digress)...

Also, it's not fair to say that there is no leverage effect from writing. As a simple, obvious example, I leverage earlier blog posts that I've written in later ones. This saves me from having to re-explain older concepts, and allows me to reach into more complex concepts, since I have already explained the simpler concepts that the later elaborations rely on.

Finally, it's worth pointing out that the purposes of writing, piano-playing, or coding, are different. Coding is generally a utilitarian activity, aimed at achieving a practical purpose, that can be sped up profitably. Writing and piano-playing are more like entertainment. It's as pointless to speed up piano-playing as it is to speed up a dance.

"Is there any skill besides coding that allows you to use your ability to make using your ability easier?"

Code is probably far and away the best example, as you point out. But this is true to a lesser degree in areas like metalworking. It is also true to an extent in biology where one biological system can be constructed specifically to help study or mass produce another.

And of course it is true in mathematics, where by moving up a level of abstraction you can develop techniques and knowledge that help in a huge array of problems.

In short, it will be true in any field where the material being worked with is also the material being worked on.

It seems like the skill of building machines would be analogous. There are all sorts of machine out there that help you build more machines, and if you know how to build machines you can improve these machines to help you build better machines.

Short stories, screenplays and novels are definitely not tools, since you don't build stuff with them, they are finished works, and if you want to make another one, you have to start from scratch. I'd argue there are more similar to frameworks, but less powerful, since the structure of a novel only gives you a basic idea of how the end product should look, instead of doing any actual work for you.

To be fair, if I want to apply computer technology to solve certain complicated, real-world problems, I need to know both code and calculus.