That makes sense. Ideally it would be nice to have one common elegant language which can do it all. But I doubt that any one language can do everything elegantl

That makes sense. Ideally it would be nice to have one common elegant language which can do it all. But I doubt that any one language can do everything elegantly. The syntax of some languages make them much more elegant for certain purposes. For example compare XML and JSON. JSON is great as a lightweight way to represent simple objects, but XML is better for representing entire HTML documents. Likewise you can do all your CSS stuff by manipulating DOM properties in JavaScript, but pure CSS is a cleaner and more readable way to do things because it only does styling statements. (Unless you go out of your way to put logic into your CSS.) The bigger the project is the more you have to favor readability and maintainability first, and using multiple specialized languages to accomplish different specific tasks is an effective way to keep the codebase readable and maintainable.