The whole point of Rust is that C, and all the code written therein (or as much as is feasible), be eventually replaced and abandoned. The potential costs of continuing to use C, and all the memory and concurrency bugs that come with it, runs in the billions worldwide if not more.

Besides which, in 2025 all the real ones are using jj, which is 100% Rust, not git—so if git wishes to remain competitive it needs to catch up.