People build all kinds of complete things with just "C" -- where by this term, I mean the compiler, standard library, build and debug system (make/gdb, say).
There are few things of interest you can build with just a hammer. The evidence for this is that no craftsman builds with just a hammer.
The better analogy to the concept of "C" above is "wood shop" (as opposed to, say, "metal shop", "polymer shop", "electronics shop"). You still get the point, which is that everything out of the wood shop to some degree "looks the same" but it's not so clearly leading the reader to the hoped-for conclusion ("the statement is stupid").
I have no problem with the conclusion that the tool matters less than what you're building.
I'd go farther and say that there is a certain tendency for C projects to "look the same" and that lispy projects "look the same" in a different way (e.g., surprisingly extensible, incorporating a language).
A basic message of CS is that most general-purpose programming languages are to a large extent isomorphic in their expressive power, and that many computing problems can be solved efficiently in the mathematical language of sets, matrices, or abstract nodes sending each other abstract messages. The translation to a real language is then the easier step (though it still can be time-consuming and error-prone, for sure).
If only we all worked this way - there would be fewer language wars, and less terrible code resulting from "thinking in the language" rather than "thinking about the problem".