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?
Drive by contributions are just as frequent in gitlab as github. I’ve been involved in moving multiple large free software projects from github to gitlab and there was zero difference seen in discoverability, in fact contributions grew on gitlab, although there is no data to suggest it was because of gitlab, as it could have been because projects aged and grew