Board Thread:Theories and Rumors/@comment-38790668-20190312173454/@comment-30499831-20190313001921

He unlocked his True Potential when he became the Golden Ninja. To reach his full potential as the Golden Ninja would be to unlock the full power of the First Spinjitzu Master. He no longer has the ability to become the Golden Ninja, so he can't do that. And he'd be too powerful.