creation is not a problem, maintenance is.

Suppose you want to add one more property to VerifiedUserWithBirthday and UnverifiedUserWithBirthday, you might get 2 more new types, and somewhere at the higher layer call chains you need to know which enclosing type you should pass so that some method in the bottom chain will accept it.

I am sure there are more elegant ways, but I am struggling to generalize it to most enterprise SaaS CRUD apps, where you have one object with bunch of properties and can conditionally traverse the code logic