If you want your language to be suitable for any purpose by using an intricate web of libraries depending on each other, you need those language features and deep theory. Think haskell, lisp, rust, etc.
If you kind of know what people will use your language for, and you build in the most important functionality, you aren't nearly so dependent on libraries. You just make the language accessible and as productive as possible. Think Go, erlang, PHP, SQL, javascript, VB.