It's very much like refactoring code. You can do it on a higher level by cutting out entire chunks of code that don't really need to be done, or on a low level by being familiar with the language's helpful syntactic sugars, best practices, to make the meaning clear and less obscured by boilerplate and "syntactic chores".

I noticed the effectiveness of low-level refactoring in prose when I first started writing academic papers. Since page limits are strict, you need to pay attention to eliminate any words that aren't necessary and are thin on semantics. This doesn't mean writing in staccato. But when you spot a paragraph where a single word spills over to an extra line, it requires a specific learnable skill to rewrite a sentence or two to eliminate the extra line. You can often tell how much someone wordsmithed around on a paper by seeing how long the last line of each paragraph is.

Of course sometimes gains are on the high level, I'm not saying that good writing is just about messing with the low level of the actual words and the grammar. Similarly to the debate whether premature optimization is the root of all evil, it's about a balance in writing too. First you must have clear thoughts on what to say and what you can leave out. But at the end, when things have settled, it is worth to go over it once again at specific places and low-level edit things to be snappier, counting words, letters and millimeters on the paper.