[starkrights]

Sometimes people like to do things just do do them, because the idea is cool. Sometimes an idea is cool because it has real world ramifications just for existing (trusting trust, supply chain attacks), though many people like to argue about whether or not this particular idea is Just Cool TM or Actually Useful TM. I don’t think the article made any false pretenses either way- it seemed evident to me that at least some of the motivation was “because how? I want to do the how!” And that’s cool! Also, I think the article pretty clearly redirects your question. Duh he could just cross compile rust. But the whole article, literally the entirety of it, is dedicated to exploring the chicken/egg problem of “if rustc is written in rust, what compiles rustc?”, and the rabbithole of similar questions that arise for other languages. The answer to that question being both “rustc of course”, and also “another compiler written in some other language.” The author wants to explore the process of making the compiler in [the/an] ‘other language’ because it’s Cool.

Just because something has already been done, does not mean there’s no worth in doing it- nor that there is only worth in doing it for educational and/or experiential purposes :)