Maybe I used Franchise as the wrong term to describe the Die Hard films
To me 'series' rather than franchise is probably the better option.
In fairness by the time we reached DHWAV we had already hit the point where it had become a staple of action movies, such as Lethal Weapon. It had already began riffing on itself and became very self aware and self referencial.
But yeah, with the huge gap between the third and fourth film, egos had changed and it has defintely seemed to slide more towards Willis essentially fitting into the character of McClane just for the sake of it.
Such a shame that a series that started so incredible with an actor who embodied the main character with such life and energy has resulted in this.