I’m not sure I understand. In your example you’ve grouped related data in a struct and validating that it matches your system’s invariants, that feels good to me.

The original example was more “wrap a simple type in an object so it’s always validated when set” which looks beautiful when you don’t have the needed getters in the example nor show all the Get call sites opposed to the 1 or 2 New call sites. All in the name of “we don’t want to set the username without validation” but without private constructors Username{“invalid”} can be invoked, the validation circumvented and I’m not convinced the overhead we paid was worth it.