Being written in Rust has mixed effects. Rust is still less mainstream than C, so fewer people can contribute. However, it does attract more interest because it’s different.

Yes, it's "different". That is all that it has to offer: it's "different". There is no other reason why people might be interested in it.

However, the reasons why you create/contribute to new-but-similar projects is to add functionality that the original project doesn’t have.

Why is that the only reason to motivate someone to do such a thing?

So why are people (and Canonical) contributing so much labor to something that still doesn’t function as intended?

Maybe we should take them that they word that they are genuinely think that coreutils would be better if it were written in Rust? Why is that such a radical possibility?

I say it’s the licensing.

Yes, I have noticed that you are very big on saying what others' motivations are.