Yep. It's really a problem that needs to be fixed in git proper. I'm surpised that github of all people didn't realize this and/or invest the time to do it right.
The one major obvious drawback for it being fixed in git is that it's not backwards compatible with old clients though. Doing it in go is probably a good improvement over the existing solutions of git-media and git-fat but I don't think is the final one.
Funny enough, although I had thought this since I started working with git-fat, I only recently admitted it[1]. Perhaps if I had admitted it when I first started work on it then there's a chance they would have seen it! :-P
[1]https://github.com/cyaninc/git-fat/issues/41#issuecomment-88...