Zoro not being able to cut Doflamingo's bird cage instead of just trying to stop it was ridiculous, especially considering how he had just been able to practically cut a mountain, using an attack in which he said that that there's nothing he couldn't cut.
There would have been more coherence in the end of Dressrosa arc if both Zoro and Fujitora were too busy with something else so they wouldn't cut the bird cage not because they couldn't do it, but because they were too busy doing something else, so they wouldn't be among the ones trying to stop the movement of the bird cage.
There would have been more coherence in the end of Dressrosa arc if both Zoro and Fujitora were too busy with something else so they wouldn't cut the bird cage not because they couldn't do it, but because they were too busy doing something else, so they wouldn't be among the ones trying to stop the movement of the bird cage.