Bhagavad Gita, Chapter 11, Verse 31

Tell me who You are, fierce in form. Salutation to You, O Deva Supreme; have mercy. I desire to know You, O Primeval One. I know not indeed Your purpose.

After everything shown so far, the most basic real question still hasn't been answered, who is this.

Arjun doesn't ask for more detail or more spectacle, he asks something simpler and more direct. Real understanding, he's realizing, means knowing what's actually standing in front of him.