I understand that but there is a difference between just git and the forge, which is GitHub in this case. If I fork a project on GitHub it has a fork relationsh

I understand that but there is a difference between just git and the forge, which is GitHub in this case. If I fork a project on GitHub it has a fork relationship on the platform itself. This makes it very easy to interact with the original project. However, without an actual GitHub account I can't contribute back to the project at all. If I have for example my own Gitlab server I have the ability to clone a project from GitHub and maintain my fork on my server. However, to contribute back, I will still need to bring my changes back to GitHub first. What a federated implementation of such a "git hosting/collaboration platform" would allow me to do would be to fork a project from another instance to my self-hosted instance. It would benefit every open-source project that would be willing to host their own instance. I could then easily contribute back into the main project without needing an account on their instance. It would also make it much harder to take down a project with a DMCA like this because forks of it would exist across instances, meaning claims would have to be sent to each maintainer of these instances. In this case, they were simply able to list all of the forks on GitHub and because GitHub is one website, all of them were taken down, seemingly without any further inspection wether the claim covers these forks as well. I realise that this is difficult to implement but I think mastodon is a great example of how such federation can work in practice.