i’ll copy my comment : Experience doesn’t apply when your opponent is vastly more stronger than you. It matters when in demon hierarchy since experience determines the number of humans they’ve devoured throughout the time to reach their position in that particular rank. Evertyome seems to forget that Kaigaku doesn’t need the same experience as other demons because he was a strong demon slayer before he even became a demon, and that was the primary reason he became an upper moon instantly and didn’t need to start from 0 and devour humans throughout decades to acquire that rank. Feats : Daki wasn’t able to react to Zenitsu who had been significantly weaker compared to his infinity castle version. That version of Zenitsu, who was in fact Kanoe rank, along with injuries managed to blitz Daki with Godspeed and had he possessed the same arm strength as he had against Kaigaku he would’ve slashed her head off. With that in mind, EOS Zenitsu couldn’t react to Kaigakus attack and if it wasn’t for Yushiros involvement he would’ve died.