I agree, and from a different perspective, I would compare this to literature. In English literature we have many different paradigms: Victorian literature, Modernism, Post modernism, Post colonial ect. The language has to be expressive, and in being expressive, it can express any of these different paradigms. The fact that the vocabulary is shared between the "eras" of literature is only a bonus which makes authors more flexible and more able to experiment with actually new concepts, rather than simply reinventing the same old vocabulary.
We then have Chinese literature and Indian literature, and these have very different paradigms. Perhaps it is even hard to effectively translate from Chinese to English. But the actual variance within a given language is still greater than the variance between the languages.
And like human languages, the vocabulary is often arbitrary. In human languages a dog is called a dog not because it makes the sound "dog" and not because it looks like the letters 'd', 'o', and 'g' but for entirely arbitrary reasons of phonetic shift and arbitrary initial designation.
And in lisp you take the 'car' of a tuple and in Haskell you take the 'head' of a list. But the two concepts are very much the same. However, the distinction between continuation passing style (CPS) concurrency and the actor model can be expressed in either langauge just as well. And the distinction between CPS and the actors is FAR grater than the distinction between calling the basic function "head" or "car".