I really don’t see what niche it is trying to fill that isn’t already occupied.
Rust is as successful as it is because it found a previously unoccupied niche: safe systems programming without garbage collector and with high level abstractions that (mostly) optimise away.
I don’t think “better C” is a big enough niche to be of interest to enough people for it to gain a critical mass. I certainly have very little interest in it myself.
Sure, but git is aimed at programmers. Who should have learned graph theory in university. It was past of the very first course I had as an undergraduate many years ago.
Git is definitely hard though for almost all the reasons in the article, perhaps other reasons too. But not understanding what a DAG is shouldn’t be one of them, for the intended target audience.