Personally I like Rust, but I'm against rewriting old well tested tools in Rust just because. There is this opinion out there that Rust devs rewrite everything for no good reason, but I only really saw that happening in coreutils and sudo. In the other cases that I heard of the rewrite wasn't from C/C++ (but e.g. from JavaScript and they need more speed) or they needed a rewrite anyway for different reasons (e.g. first working parallel style calculation in Firefox).

So I'm very skeptical of the coreutils rewrite. In the current state it's incomplete, slower (not optimized), and replacing all GPL code with MIT/BSD code also feels strange to me.