Why is Doffy even relevant in this discussion
Because Doflamingo had hax that was able to stop Sanji in Dressrosa
People use that as an argument against Sanji's strength, despite the fact that:
Doflamingo neg diffed Jozu a true YC with the same hax,
Zoro was unable to stop Doflamingo's passively closing bird cage
Doflamingo was originally meant to be Kaido's helper instead of BM
Doflamingo required G4 king moves to take down, something well above anything a non yonko has shown.