Some other comments mention that you can just clone your git repositories and use that a backup, but that's not practical when you're using git workflow as a core part of running your development team.

Relying on external services is never a good business move, so the a solution is to use GitHub Enterprise, which lets you run a private copy of the GitHub site on your own servers, with your own backup solution and security provisions.

Maybe this is what your coworker is advocating.

(Then again he could have an amazingly active social life with that many texts!)