I still remember the times where Pudding was treated as the devil by users on OJ, they really wanted to be an evil and irredeemable girl with no positive traits and that would be beaten by Nami or someone else. It's quite baffling that they still hadn't learnt their lesson after Nami, Robin, Hancock and Viola's cases before.
What people wanted was an actually interesting and compelling female twist villain like Monet, which Pudding seemed to be at first. Nami and Robin were never really 'villains' to begin with, they simply abandoned the crew at some point and still tried to protect them in retrospective.
Viola was waiting for an opportunity to topple Doflamingo, she hated him deeply and wanted to save her family + kingdom.
Hancock wanted to protect her sisters as well, especially because she didn't know how people might react if they find out about her very traumatic past.
Pudding.... is a priviliged princess who was called ugly as kid and saw that as justification to turn into a 'monster' who then got redeemed by a simple compliment. Let's just forget how she made fun of Sanji's trauma, despite the fact that hers was not so different... or that she literally just went into the prison library to talk to Luffy and Nami to see them suffer... you can say what you want, but the fact that she never apologized for or acknowledged any of that and is still seen as a 'good person' just rubs me the wrong way.
What people wanted was a good villain. Pudding completely played on the damsel in distress trope- a trope everyone was already used to by then- and so when she turned out to be evil, it hit different. So many people were excited and thought she might turn into some sort of mastermind that could even manipulate Big Mom with her powers. But what happened with her? It was revealed that she, a princess, Big Mom's favorite and most important daughter, the second most beloved sister of the whole family, was called ugly when she was young. and BAM! now she's a good character because tragic backstory. Pudding made no real effort to redeem herself. If Oda wanted to redeem her fine, but the way it was done was just so weak and underwhelming... like 'yeah here you have this cold and calculated mastermind but OOP she's actually just a sad girl who needed a compliment.'
Lmao yeah and that's the short version of my take on it xd