Maybe Fujitora wont need to destroy the system. By the time he is gonna do it there wont be no more Warlords except for maybe Mihawk. This is very bad, I mean only the warlords has been defeated from the 3 main power, not even the Yonko. Whitebeard does not count since he was already in the verge of death.
Not a single Admiral has been killed or defeated. I mean, they always maintain their balance but now Luffy has made the Warlords look like rookies.