The initial shock is always the most intense, and after experiencing it multiple times, no matter the escalation of intensity, those who have become accustomed or even numb will never feel that same strong impact again.
It was the same for Marseille.
When he first met the Emperor, he couldn't even think, his mind filled only with the fear and reverence one might have when facing a deity. By the time he spoke with Roland, he could already express some of his own views and ideas. And when he sat down across from Minerva, he felt only a slight excitement because he was in the presence of a legendary beauty.
After encountering so many influential figures, it was inevitable that he would think, "Ah, so this is what important people are like." While Marseille was not confined by stereotypical thinking, he found it difficult to completely escape the inertia of experience.