Elemental builds require the player to build more gear, worry about and adjust to elemental weaknesses and strengths, and micro manage decorations for elemental boosts.

All for what? To do less damage than Impact which also has the KO utility.

I don't understand that at all. Why does the build that requires significantly more effort to build and maintain underperform so much? Or why is a phial with amazing utility like KO also given the most damage?

Am I taking crazy pills?

CB changes with the patch:

• The recent phial nerf reduced our Impact/Power phial discharge damage by ~11%. Source
• Elemental phials still significantly underperform due to varying elemental weaknesses across a monster's body.