Right, crucially cargo is in the box with your Rust compiler, you have to go out of your way to have just the actual Rust compiler but not cargo.

As with the lesson gofmt taught, you must supply the basic feature in the box. Humans are lazy, so if it doesn't come in the box only people who know they can't live without it will even bother, put it in the box and only people who can't live with it will remove it.