I really do not understand why people use GitHub over Gitlab AT ALL.
GitLab consistently brings out AMAZING features at least 1x/month. Their company is ethical (donates regularly to amazing coding groups like BlackGirlsCode, DjangoGirls, PythonLadies, etc.).
Just look for yourself: https://about.gitlab.com/features/
well, git is sorta federated. You can push to multiple remotes and keep them all in sync.
I prefer my selfhosted gitea over gitlab