The original utopia plan if yall dont remember
Crocodile, mihawk, and buggy the guys that made and know the plan aren't just assuming which is more difficult without anything actually backing it up
And like
@TheAncientCenturion said doflamingo essentially achieved what crocodile wanted in dressrosa through his ties
Thats like saying wano or dressrosa had to be stronger than rocks which is obviously not true