Sure, you could say the tracking and range on Zenith doesn't matter, and that the Last Prism doesn't need fast aiming to be good, but it doesn't change the fact that Zenith does more damage and reaches max dps faster while being able to hit every corner of the screen, even through walls.

Zenith has more dps, wider range, tracking, can aim faster, and doesn't require mana/accessory slot wasted on mana flower.