Memento pattern and violation of encapsulation

Across the internet I come across with examples of implementation of memento pattern which I consider are fully incorrect. They can be written in both Java and C#.

Here a several of them

1. Incorrect implementation of Memento pattern 1
2. Incorrect implementation of Memento pattern 2
3. Incorrect implementation of Memento pattern 3

The code:

public class Originator
{
    private string _state; //the private field of originator that shouldn't be exposed!!!!

    public Memento CreateMemento()
    {
        return new Memento(_state);
    }

    public void SetMemento(Memento memento)
    {
        _state = memento.GetState();
    }
}


public class Memento
{
    private string _state;

    public Memento(string state)
    {
        _state = state;
    }

    public string GetState()
    {
        return _state;  // here caretaker can access to private field of originator!!!
    }
}


public class Caretaker
{
    public Memento Memento { get; set; }
}

In code I left comments that should describe situation.

The caretaker class can read private field of originator through memento that violates one of the main principles of memento pattern:

The object's encapsulation must not be violated.

So the question is am I right?