I don't think Milotic is going to sit there and try and haze SDSceptile or SDVenu. Haze is for Pokemon who can't hit Milotic hard enough like DDFeraligatr or on slow Pokemon like CroTomb or CMSlowbro/NPKing.Without Raikou and easy spikes, there is no one pokemon that can consistently wall-break every EV spread of a Milotic. While I agree that you should keep wallbreaking in mind when making a team, right now the central idea of team decision this round was "How can I wallbreak Milotic?" (EDIT: Using multiple pokemon sacrifices that is)
And comparing Milotic to Registeel is completely out of context considering there are countless foolproof switch-ins to Registeel that can easily set up on him because he lacks Haze.
Milotic shouldn't try Hazing something like an SDScyther, they hit too hard for it to handle, it's better off just attacking.