Cause people who think Sabo is fighting Akainu despite zeroa buld-up or that Akainu is somehow getting Blueno'd because of powerscaling sake aren't the biggest morons....
Zero build up = Sabo remembering who Ace is just after he recieved news of his death = news include Akainu killing him
Second in command of the revs
There's enough tensiob for that fight to happen. It may happen, or not, at least not acting like an admiral tard who desperately wants Akainu to be the final villain, even tho he's far from being the strongest character or of any relevance to the void century.