If there is a dependency on JS for styling, the dev still has to write some fallback CSS. The broader decision making from marketing and design will be to go for consistency, and that means not using this library the moment QA turns off JS (or simply witnesses a slow download of the JS) and opens a bug.
I can also see people being so picky about the precise lines on which words land on that it forces the dev to abandon usage of this. Yes, I do see some options in the docs, but who will maintain all that when someone just wants to change a word or requires dynamic content?