Old ill grandpa pirates shouldn't fight against youngsters in their prime. Wb should have deserved a normal death by age.
If anything … Sakazuki was portrayed as the most competent admiral in the MHQ war even if he ist an ass.Edit: It was Impressive to see how troublesome an old ill guy can be against an admiral. But at the end Wbs handicap played against him.
Even more impressive is the fact that Wb was able to surprise sakazuki alter Aces death blow. We have to remember that Admirals should have sensed someone attacking them from behind. At least they would if the opponent isn't so fast that their haki and reflexes wouldn't detect the threat. One can argue that sakazuki was distracted but that is a poor excuse for a fighter on that level in that kind of war with that kind of character.
That's funny and true actually.
I guess Akainu chewed on his own words. He said previously to WB;
"You should focus on your opponent in front of you"
Akainu chose to completely disregard WB.