I rolled my eyes twice, then merged a few PRs manually and moved on with my day. (i.e. the git server itself and all the API required to interact with the CI automation _appears_ to work just fine)
And ci integration; which runs automated tests; which must pass to release package/docker image/whatever; which is required for deploying new version for your system etc. The whole thing is as distributed as business of a guy selling hot dogs on the street.
Almost nothing I work on has a dependency on GitHub. Whether work or personal. We have all dependencies vendored at work and my personal stuff is the same.
There really is no good reason bee so dependent on GitHub.