I can’t help but notice most (all I’ve seen anyway) of the federated projects are hosted on GitHub. GitLab is also not federated, but can be self hosted and has at least discussed it.
I am fully aware of my bias for GitLab over GitHub, but I still wonder why is those things? Is there a federated source hosting project?
GitHub is (mostly) free and central, as well as being the default for the majority of developers. Gitlab handles some things differently, scales less well (from what I can tell) and is honestly just different (change is bad /s).
I think the fact it isn’t federated is a point in favor of GitHub. If something goes wrong in a federation protocol then there’s no impact to the code bases.