That's the thing. They aren't changing the power of weapons. They're changing the power of the enemies and giving us new tools to combat these new enemies. The older gear isn't getting nerfed it's just not getting buffed. They're saying what you have now is not strong enough to fight this new stronger enemy so you have to get stronger. And it's not just weapon damage and armor defense being put on the new gear they're are new perks new item types that are being applied too so even if they did boost up the damage it's still less effective so there's no point in it.