Writing SVG code once and being able to use it in multiple places helps you write more modular code and it helps make maintenance easier. SVG makes it easy to reuse text through the tref element.
The SVG text element allows you to easily position and style text, but what do you do if you want to position and style different parts of the text differently? Do you need to create multiple text elements? Nope. There’s an easier way.
Think of all the times you might add the same color to different elements or classes in your CSS file and then think of all the fun you have changing everything when you decide another color would work better. Wouldn’t you prefer to make the change once and have the rest update automatically?