Writing is a skill and an artform. In order to get good at it, you have to practice. However, if you’re writing in the same style or genre every day, you are limited to only knowing how to do one thing.
Having an expanded writing repetoire is like having a every type of medium possible for a blank canvas. You can create anything.
The important thing to remember when switching between the six genres of writing (descriptive, poetic, narrative, expository, persuasive, and technical) is that your audience is different so you’re writing style has to be different.
Writing a fiction novel is very different from writing website copy for an IT company. However, if you can do both successfully, then you have mastered the art and skill of universal writing.
Take time to write in each genre every week. Practice makes progress and progress makes you a better writer.