I think that if we could rewind time and humanity had to reinvent math from scratch, it would probably end up very different from what we have today; most of the underlying logic and ideas would be the same, but the abstractions, notations and representations of those ideas would be completely different (and possibly better/simpler and more logical).
When it comes to code; whenever something is kept a certain way because of historical reasons, that's called technical debt and it's a bad thing.
In maths, basically all of the abstractions and notations are the way they are because of complex historical reasons. Math never gets refactored.