Maybe but even if that's the case, you've now got just plain and colored vs before you'd have plain, color A, color B, color C if you go beyond just async as the only other color (e.g. whether you're accepting something by reference or value, whether it's a mutable reference, whether or not the function is compile-time, etc etc etc).

Still seems better to me if you collapse colors >= 1 into a single language system.