> It feels really wasteful to burn CPU and spin up fans every time I save a file. I find it hard to justify using 30+ GB of memory to run an LSP and compiler.

Have you tried using RustRover. I've never seen it go above 2-3GiB of RAM, but I don't write the most complex of software in Rust.

> I hate how crates.io requires a GitHub account to publish anything.

You don't need Github account to publish iirc, you need it to authorize to crates.io. You can use any Git host, but your account is tied to GitHub.