So does Ghost Zeus. And you got Kratos even at his weakest, literally having given up all his powers and magic to be with Caliope through a deception by Persephone in Chains of Olympus, murdering souls in Elysium with his bare hands to regain his status as the Ghost of Sparta Kratos isn’t weaker in that video, he just can’t perform any of the magic spells he could perform that weren’t from equipment (I.e. Poseidon’s Rage, Atlas Quake) The video specifically says magic from the Greek World is what Kratos can no longer use from destroying everything in it, not power. Magic that’s easily replaced with the magic he picks up in Yggdrasil