I don’t think this notion of complexity is meaningful/well accepted. Languages have expressivity as a more-or-less accepted concept (in which C is very inexpres

I don’t think this notion of complexity is meaningful/well accepted. Languages have expressivity as a more-or-less accepted concept (in which C is very inexpressive, Haskell, Ruby etc. are very expressive), and language complexity as perhaps another, where the concepts of the language are taken into account. For example something like Idris with dependent types would be a quite complex language, while C may indeed be relatively simple. This is usually the inverse of expressivity. You seem to talk about the complexity of a program when written in a specific language. Here, a more expressive language would fair better, at usually the cost of a more complex language as mentioned above. But as we all know, essential complexity (of a problem) is non-reducible.