Downvotes are probably because that is what companies without chronic outages do.
If you'd ever worked on a codebase as terrible as I imagine GH's internals are and looked at the git history, you'd find two things:
1) fixing it would require rolling back 100's-1000's of engineer-years of idiocy that make things like testing or refactoring untenable
2) many prior engineers got part of the way through such improvements before leaving or being kicked out. Their efforts mostly just made it worse, because now you never know what sort of terribleness to expect when you open an unfamiliar file.
If you'd ever worked on a codebase as terrible as I imagine GH's internals are and looked at the git history, you'd find two things:
1) fixing it would require rolling back 100's-1000's of engineer-years of idiocy that make things like testing or refactoring untenable
2) many prior engineers got part of the way through such improvements before leaving or being kicked out. Their efforts mostly just made it worse, because now you never know what sort of terribleness to expect when you open an unfamiliar file.