Sure, I was talking about a 'new' programming language. PHP has already a bunch of work required to fix its own standard library.
The point is, the standard libraries, especially in languages such as C++, Python or Javascript, are far from being the only libraries used by a project. Even if they follow consistent conventions, it can happen that an external library author does follow another convention. Using both libraries can lead to use multiple naming conventions in a single program, which doesn't help readability. It would be nice to be able to prevent this.