Well, there are many ways to learn about things, there's no "have to" about it. Learning principles in the context of a language is learning in the context of

Well, there are many ways to learn about things, there's no "have to" about it. Learning principles in the context of a language is learning in the context of application rather than pure theory. For some, this helps ground ideas by connecting them to others they already understand. Of course, no advice is universal, and each person needs to decide if it applies to them. This advice most applicable in the context of deciding what language to learn next. Assuming you want to improve your ability to tackle more kinds of problems, rather than fulfill a particular checkbox. Like learning Java when you already know C# is going to contribute to personal growth less than a LISP or prolog or Rust.