[ComputerGuru]

A comment at TFA by benatkins has a nice answer:

they probably mainly want feedback from the project maintainers at this stage, and the project maintainers can apply a patch just about as easily as they could apply a pull request. (It's so big that the web view isn't likely to be useful.) Also this will probably be going into a new branch if anywhere, so does a pull request to an existing branch (which is all that's possible AFAIK) even make sense?