Nothing in Rust requires you to use Cargo. It's really convenient to have a good build system like Cargo—but if you like C style of manually invoking the compiler, rustc can do that too.
Rust is no worse by bundling Cargo. It strictly dominates the alternative, which would be to just ship rustc and allow the user to pick whatever build system they like. You still can pick your favorite build system; but if you don't have a particularly strong preference, Cargo is a very good default.
Nothing in Rust requires you to use Cargo. It's really convenient to have a good build system like Cargo—but if you like C style of manually invoking the compiler, rustc can do that too.
Rust is no worse by bundling Cargo. It strictly dominates the alternative, which would be to just ship rustc and allow the user to pick whatever build system they like. You still can pick your favorite build system; but if you don't have a particularly strong preference, Cargo is a very good default.