I don't see how this could ever work on evolving languages, different GIT versions would produce different commits and read commits differently based on the latest C++ standard. This would potentially lead to version control bugs where different GIT versions creates different results from the same commit, that is horrible, version control needs to be 100% bug free in that regard.

The only reasonable application would be to use a language AST parser to better identify relevant text diffs, but the commits still needs to be stored as text.