We know that in the "One Piece" anime, the strength of Doflamingo is at most comparable to the senior cadres of the Four Emperors Pirate Regiment, far from reaching the level of the imperial vice, but Doflamingo's development of the line fruit can be described as reaching the extreme, not only playing the simple line out of the flower, but also mastering the move "bird cage" at the bottom of the pressure box. Once the "birdcage" is opened, no one can escape the shackles of the "birdcage". If no one can defeat Doflamingo, the "caged man" will only be squeezed into pieces. That being the case, why didn't Doflamingo use a "birdcage" when fighting at the top?
First of all, there is no need for Doflamingo to exterminate the Whitebeard Pirates. After all, even if the Whitebeard Pirates were a roadblock for Doflamingo to advance to the Four Emperors Pirates, there was still no need for Doflamingo to obliterate the Whitebeard Pirates. For Doflamingo, his strength is too weak after all, he himself does not have the strength of the four emperors, even if it is the "talented" Don Quique de family, it is difficult to pick out a few strong people. Perhaps, as long as Kaido's "three plagues" lead the team, it will be enough to defeat Doflamingo and his forces. Therefore, Doflamingo still needs to accumulate strength. But if the Whitebeard Pirates are wiped out, then the Naval Headquarters and the World Government will have more power to contain Doflamingo.
Secondly, if Doflamingo dared to release the birdcage in the war on top, he would most likely be beaten by a group of people. After all, Doflamingo's "birdcage" is too buggy, and if Doflamingo is not defeated, it is impossible to crack the "birdcage". At that time, Doflamingo will be a siege of the Whitebeard Pirates, or even the Blackbeard Pirates. Even if Doflamingo has made an "outstanding contribution" to the Navy, at most only the Red Dog will stand up for protection. After all, Luffy is Cap's grandson, and he is also the "young lord" of the yellow ape, once Luffy is executed after Ace, the rampaging Cap and yellow ape are not something that Doflamingo can handle.
Furthermore, doflamingo's ultimate goal is to disrupt the world ruled by the Draco, not to help the world government. Since losing his identity as a Draco, Doflamingo has held a grudge against the Draco. To this end, he did not hesitate to become a middle force in black and white, selling weapons and trying to cause more wars and disgrace the world government. As a result, Doflamingo would at most "work out" in the top war and would not use all his strength against the Whitebeard Pirates.
Finally, of course, because Marin Burn is the seat of the naval headquarters and the face of the world government. Although there was a "discord between Doflamingo and the Naval Headquarters", Doflamingo did not have to stand up to the wind and offend The Weah of the Naval Headquarters. After all, if Doflamingo didn't say a word, he would suddenly release the "bird cage", which would not only cause a fatal blow to the Whitebeard Pirates, but also affect the battles of the naval soldiers, and would also wantonly destroy the building of the naval headquarters, embarrassing the Sengoku, the Red Dog and others.
The above is the view of the anime enlightenment jun, if you also agree, you are welcome to like and pay attention to the anime enlightenment jun (typing is not easy, please support more); if you have other different views on the analysis of the anime enlightenment jun, welcome you to leave a message at the bottom of the article to express your point of view (your bricks and suggestions are the biggest driving force for the enlightenment jun to move forward)!
Pay attention to the anime enlightenment jun, the enlightenment jun will provide you with high-quality and unique anime analysis without stopping.