Languages that make use of references rather than pointers don’t have this Dualism.

It's not about references vs pointers. You could easily have a language that allowed "null references" (edit: too much C++; of course many languages allow null references, e.g. Javascript) or one that properly separated null pointers out in the type system.

I agree with your point though, using a special Null value is usually worse than using Option or similar. And nullptr_t doesn't help with this at all.