Rust by default only does a full build really rarely. Ive gone through days, even weeks, of working on a project without a full build.

Partial builds are of course way faster, especially if you use many dependencies (i know you don't). I mainly work with the bevy game engine in Rust, which has a lot of dependencies. Even if i don't use its dylib feature, i get 2-3s compiles. And that's on a project with multiple hundreds of thousands LoC when you include dependencies. With dylib, it goes down to 0.5-1 second builds.

If your main conclusion is based on full builds, i would urge you to re-evaluate. The normal experience is just "cargo run" which rarely does a full build.