With Hexblade you not only get proficiency with your polearm, but charisma is your stat to hit and damage.
It remains to be seen just how much of Hexblade is being translated to Pact of the blade.
You can always just get the mod.
My dude its literally in the video, he hovers it. Pact of the blade let's you summon a weapon and use caster stats for combat but there's no proficiency