The important information to know is that GitHub is just a layer on top of a gitserver, and the main parts we use are the patches and the issues, which we have in gitstuff events.
You could keep GitHub as a remote NIP repo and everyone could have their own repo clone and decide, by themselves, which patches they pull. That would end the need to grovel to the repo owners, to get a NIP merged. More-popular patches would be pulled by more people, even if the GitHub repo owners don't like it.
The people you actively work with would tend to have patches that you are more-likely to see, which eliminates the need we've developed to go off and have topic-chatrooms, so that you can finally talk with the people interested in a Nostr topic on Nostr.
But whatever.
We haven't ever gotten any use out of the NIP repo. Only grief. Over and over, nothing but grief and time wasted that we coulda spent developing and shitposting.