shove some text into stdout

That's not what this operator does normally, and if you try to "shove" something into anything else (an int into a variable? a function into an object?) you'll get surprises... Basically it's "special" and nothing else in the language behaves like it. Learning hello world in C++ teaches you absolutely nothing useful about the language, because it doesn't generalize.

C, in contrast, has many instances of complex functions like printf (another commenter mentioned variable arguments), and learning to call a function is something very useful that generalizes well to the rest of the language. You also learn early enough that each different function has its own "user manual" of how to use it, but it's still just a function call.