Then Kyurem White would be in OU rite? Because although its movepool is shallow, it has enough to make it a huge threat unlike Kyube which lacks even a good physical ice STAB
The sole reason KyuW is much better is because it can nuke stuff safely and many steels happen to be Physically bulky
Like, if Kyurem Black want to nuke stuff with Outrage, because Dragon Claw only have 80 BP, it need to know that no faster dragon is on the opposing team(team preview helps) or a Steel switch in won't ruin its parade. After this, throw in external factors such as Scarf or Band in the picture. This is before including burn in the whole stuff, which ruined its physical attack power if it hits
How about Kyurem white? "Draco. Freaking. Meteor". If it get burned, it can simply switch in again and spam more DM. I don't think I need to give calcs, just take a look at how monstrous DM Latios is, but increase the damage output by around 20%. Really though, as useful as Ice Beam might be for Kyurem White, Draco Meteor is basically everything it need
The difference is much bigger than simply "LOL KYUBEE DON'T HAVE PHYSICAL ICE MOVE WHICH IS WHY ITS OU"
Finally anyone who said Kyu-W has shallow movepool should be shot. Dragon/Fire/Fighting/Earth coverage is bad how?
Going slightly for theorymonning area, Physical equivalent of Draco Meteor, Icicle Crash, Icicle Shard, Earthquake, and a Fire type Physical move with decent BP might be needed
TL;dr If Kyurem Black want to match Kyurem White, STAB Physical Ice move is NOT what it need.
FUCK HOW CAN I FORGOT ABOUT THAT SEXY ICE BEAM THAT CAN KILL MEGASAURA minor nitpick, but Kyu-B doesn't care about Multiscale anyway because of Teravolt. Also, it outspeeds neutral-natured Dnite (if you run Speed EVs, anyway. But who doesnt?).
shame to the famiry