There are many good replacements, you just need to stop using Github :)

Some examples: Forgejo/Gitea (self-host or hosted eg. codeberg.de), Gitlab (self-host or hosted), Sourcehut (self-host or hosted eg. sr.ht)

C is old, ubiquitous and still does not have a good replacement for its low-level cross-platform usecases, so I’ll believe it when I see it 😄

Why not go even further? Just switch off the pesky computer entirely. No noise, not even coil whine.