It's not like JS isn't already implemented in a language that's a lot more similar to Rust anyhow though. When the browser or Node or whatever other runtime you're using is already in a different language out of necessity, is it really that weird for the tooling to also optimize for the out-of-the-box experience rather than people hacking on them?

Even as someone who writes Rust professionally, I also wouldn't necessarily expect every Rust engineer to be super comfortable jumping into the codebase of the compiler or linter or whatever to be able to hack on it easily because there's a lot of domain knowledge in compilers and interpreters and language tooling, and most people won't end up needing experience with implementing them. Honestly, I'd be pretty strongly against a project I work on switching to a custom fork of a linting tool because a teammate decided they wanted to add extra rules for it or something, so I don't see it as a huge loss that it might end up being something people will need to spend personal time on if they want to explore.

Over-minifying is kind of pointless, just do a basic minify and then gzip and call it a day.