That's no difference than using newtype structs. If you remove the extra layer you are left with `string` for both of them.

> The difference is that happens in the domain layer instead of the type layer

This view greatly reduces the usefulness of the type layer though, as that's the only automated tool that can help the domain layer with handling cases like this.

It's not really automated though, it's just another layer of code written by a human, prone to the same types of human error.