Github isn't git
By removing it's decentralised nature you've fundamentally built a different VCS. Perhaps SVN is acceptable for your use case, that's great! It's definitely not git though - basic expected use cases were lost as predicted at the start of this thread.
The core task of a VCS is versioning and collaborating on text of some kind. Git doesn't do this in an optimal way, so eventually it will get replaced by something better. In the meantime we'll all get on with learning its ins and outs, just like previous generations learned how to use punchcards.