I strongly disagree, mandi is going to be a huge help for alot of defensive and balance teams, its a great defogger and checks a great deal of stuff with it bulk. I have access to foul play knock off taunt u-turn whirlwind which are all great moves that can bolster different play styles according to what moves you choose. But after Dark's boost in Gen 6 I can't see mandi dropping even further, it has way too much going for it rn.
Please read my posts for calcs against common UU wallbreakers. This is illustratedly false.