If they don't remove the item level sync? That's fine. But it'll at least be easier to access later on. Easier to beat? Maybe not. But I wouldn't expect them to keep the sync. In case you have missed a few raid tiers and an expansion, they allow easier access and completion as time goes on for just about everything. If they keep the sync for Ultimate I will be very surprised. I know full well how big Bahamut is as far as this game goes. I wasn't equating him to fireworks at all. They could have put anything as a reward via the lockboxes. That was the point I was trying to make.
Do I care if there's an emote there or not? No, and I won't buy it on the mogstation either. I'm fine not having it. But to say it wouldn't make sense as a lockbox reward? You are probably right, but if it were...no one would really question it. Not everything does or has to make sense. We have flying elephants and spinning turtles for crying out loud. Any sort of lore arguments went out the window long ago.